Only one of those three sentences is a compound sentence. It has a coordinating conjunction in it.
https://chompchomp.com/terms/coordinatingconjunction.htm
Choose the option that best combines these sentences into a logical compound sentence.
Stina is really, extraordinarily good at playing billiards. I've never dared to play with her.
Choose 1 answer:
A
Stina is really, extraordinarily good at playing billiards, so I've never dared to play with her.
B
Stina is really, extraordinarily good at playing billiards, I've never dared to play with her.
C
I've never dared to play with Stina, really, extraordinarily good at playing billiards.
2 answers
I've never dared to play with Stina, really, extraordinarily good at playing billiards.