Context-free languages are closed under:
Union, Kleene closure
Complement, Kleene closure
Cfl are not closed under intersection and complement now choose the correct option, so (B) union and klenne closure.
You are welcome
check it out http://cs.stackexchange.com/questions/58255/why-dcfl-is-not-closed-under-kleene-star
The context-free languages are closed under union, concatenation and Kleene closure.
so option B