: People who got J&J’s COVID-19 shot can get a booster. Which one should they get?

The 15 million people in the U.S. who got Johnson & Johnson’s COVID-19 vaccine now have the option to get a second shot of their choosing. 

The Food and Drug Administration on Wednesday authorized a second dose of J&J’s JNJ adenovirus-based vaccine for all adults initially vaccinated with this shot.

The regulator is also allowing people to…