Seven books P, Q, R, S, T, U and V are placed side by side. R, Q and T have blue covers and other books have red covers. Only S and U are new books and the rest are old. P, R and S are law reports; the rest are Gazetteers. Books of old Gazetteers with blue covers are
A
Q and R
B
Q and U
C
Q and T
D
T and U
Correct Answer: Option C
Explanation
To solve this elegantly, we recall the 'Efficient Sequential Filtering' strategy