For this case we can translate the sentence given as:
Bowling is _________ (less) interesting ____________ playing video games.
We must complete the sentence with a comparative inferiority.
Subject + verb + less + adjective / adverb / noun + that ...
Subject + verb + "menos" + adjective / adverb / noun + "que" ...
So, the correct option is:
Jugar a los bolos es menos interesante que jugar videojuegos.
ANswer:
Option A
