The FANG trade hasn’t lost its bite.Big technology stocks are again charging to new heights and propelling the broader stock market, which is swiftly rebounding after a punishing selloff.The NYSE FANG+ index—which comprises Facebook Inc., Amazon.com Inc., Netflix Inc. and Google parent Alphabet Inc., along with Apple Inc., Twitter Inc., Tesla Inc., Nvidia Corp. and the Chinese behemoths Alibaba Group Holding Ltd. and Baidu Inc.—is up 11% year-to-date after a dramatic rally last week.The four FANG stocks added $251 billion in market value last week, their biggest gain on record dating to Facebook’s 2012 initial public offering. The S&P 500, in comparison, is down 13% in 2020 but has rallied 9% month to date.The big tech stocks “are like chicken noodle soup,” said Mike Larson, a senior analyst for Weiss Ratings. “They are the old reliable and old standby for portfolio managers…Nobody is going to get fired for adding Apple stock in a downturn like this.”The returns for big tech companies have helped answer, at least for now, a question that has long swirled: How would the deep-seated market leaders fare in a downturn? Many analysts and investors worried that an eventual market rout could extinguish the FANG trade’s flame, pulling the broader market down with it.The four companies, along with Apple and Microsoft Corp., together accounted for roughly 20% of the S&P 500’s value in mid-February, giving them outsize influence on the market’s direction.Their resiliency during the coronavirus pandemic underscores investors’ faith that they have enough momentum to continue powering the market rebound.After driving much of the historic 11-year bull run that ended in March—Amazon’s share price, for example, has swelled 3,857% since March 2009—the tech companies now face one of their biggest tests yet. Although investors and analysts have suggested that global stay-at-home orders have been a boon for the tech firms, their coming earnings reports will begin to reveal the true damage from coronavirus.The results will also likely give clues about which of the companies are best positioned to emerge stronger.Investors are already betting on the continued success of Netflix and Amazon, whose shares have recently broken away from the pack and set records last week. Both stocks have risen 30% or more this year and are among the best performers in the S&P 500.Shares of graphics-chip maker Nvidia are also getting a big bounce, up 22% in 2020, thanks to videogame demand. And Tesla has ended 10 of its past 11 trading sessions higher, extending its gains for the year to 78%, as investors bet on the future of electric vehicles and the vision of Chief Executive Elon Musk.Tesla, along with other momentum stocks, was hit hard during the market rout, losing more than 60% of its value in a month after a meteoric rally to start the year. Investors betting on momentum typically buy shares of companies that have risen the most in the past 12 months, counting on their continued outperformance.The FANG stocks held up better than other momentum shares during the selloff. Amazon, for one, fell 23% from its February high to its March low. In recent years, momentum bets have often included tech and other growth stocks, which typically look expensive compared with the broader market but offer higher-than-average profit growth.Institutional investors were among those who remained loyal to the big tech stocks during the selloff. Amazon, Microsoft, Facebook and Alphabet sat atop the list of stocks in which hedge funds had invested the most money as of March 17, according to an RBC analysis of S&P 500 companies. Netflix and Apple ranked in the top 12.And even in the weeks since, few investors are betting against the stocks. Short interest in Amazon hovered at 1.1% as of April 13, unchanged from a year earlier, according to Goldman Sachs Investment Research.Some analysts say they expect many of the big tech companies to emerge from the pandemic stronger, in part because of the potential for permanent behavioral changes in its wake. With consumers shopping online, consuming in-home entertainment and communicating through the internet more often, “it’s very hard for me to imagine a scenario where the S&P 500 recovers and Google and Facebook would not,” said RBC Capital Markets analyst Mark Mahaney.Netflix will be the first of the group to test that theory when it reports results Tuesday. The streaming platform’s profit is projected to more than double from a year earlier, while the companies in the S&P 500 as a whole are projected to post a 15% drop in earnings, according to FactSet.Facebook, Alphabet and Microsoft are also expected to post higher earnings, while profits at Amazon and Apple are expected to decline modestly.Despite the tech giants’ recent outperformance, Mr. Larson, the Weiss analyst, cautions that they are vulnerable in a recession—even though their balance sheets remain strong.Facebook has already said its recent uptick in usage won’t protect it from digital advertising declines. Google is expected to face the same problem. Meanwhile, demand for Apple products may fall as unemployment rises, and Amazon could continue to face staffing issues and stretched infrastructure.“These aren’t, in my mind, safety names, and in some ways they are still being treated that way,” Mr. Larson said.“In past bear markets, you tend to have a change in leadership—the stocks that led you into a bear market weren’t the kinds that led you out,” he said. “Could I tell you off the top of my head what will ultimately lead us out of this? The crystal ball is a little foggy there.”This story has been published from a wire agency feed without modifications to the text.