The plural form of simpático is simpáticos.
The answer to the question is:
Nadando
Vivir
Leemos
Debes
Ellos insisten
El toma
Corremos
Ellos escalan
your answer would be C, son
Translation: I like sports, what are your favorite sports?
If you were answering the question you would say:
Mis deportes favoritos son...
and add the name of your favorite sports after it.
Example:
Mis deportes favoritos son <span>fútbol, baloncesto, y el golf</span>