5 high-growth themes and the stock-market ETFs that can deliver big gains in 2021 By: MarketWatch January 06, 2021 at 11:55 AM EST Cannabis, 5G, clean energy and other strategies for stock-market outperformance. Read More >> Related Stocks: AT&T Inc Advisorshares Pure US Cannabis ETF Aphria Inc Bottomline Tech IN Ciena Corp Digital Realty Trust ETFMG Alternative Harvest ETF Fiserv GX Fintech ETF Global Clean Energy Ishares ETF NDX Nasdaq Smartphone Index Fund Nio Inc ADR Paypal Holdings Plug Power Inc Qualcomm, Inc. S&P Biotech SPDR Verizon Communications Wilderhill Clean Energy Invesco ETF Xero Ltd