Option B) L1 intersection L2 is correct answer, as If l1 and l2 are two CFG’s their intersection need not be context free.
eg- L1={a^n b^n c^m| n>0 and m>=0} and L2={a^m b^n c^n|n>=0 and m>=0} , Therefore ,
L1 intersection L2 = {a^n b^n c^n| n>=0} need not be context free.