what we wrer asked to find is BUC
which means B union C
that also means numbers that are found both in set B and set C
so for
set B {4, 7, 11, 12,14}
set C {2, 4, 8, 10, 11, 12, 13}
therefore,
BUC {2, 4, 7, 8, 10, 11, 12, 13, 14}
so the correct option is B