Clearly, in the given code, A = 1, B = 2, C = 3, .... so that
COVER =  3 + 15 + 22 + 5 + 18 = 63
Now, in BASIS, (B = 2), (A = 1), (S = 9), (I = 9).
Thus, BASIS = 2 + 1 + 19 + 9 + 19 = 50.
Hence, the answer is (b).