Question

why might someone celebrating christmas in rio de janeiro, brazil, be wearing a bathing suit and spending the holiday on the beach?
in brazil, christmas is celebrated in june instead of december.
rio de janeiro is located on the equator, so it never has cold weather.
seasons in the southern hemisphere are reversed, so december is in summertime.
brazil has no christians, so people there do not celebrate christmas.

Explanation:

Rio de Janeiro is in the Southern Hemisphere. Christmas is in December. Since seasons are reversed in the Southern Hemisphere, December is summer - time there, allowing for beach - going and wearing bathing suits.

Answer:

C. Seasons in the Southern Hemisphere are reversed, so December is in summertime.