A/2. B/4, C/8, D/16,..
(a) E/18, F/20
(b) E/32, F/64
(c) E/18, F/22
(d) E/20, F/32
Answer: (b) E/32, F/64.
Solution:-
A + 1 = B & 2 x 2 = 4,
B + 1 = C & 4 x 2 = 8,
C + 1 = D & 8 x 2 = 16,
Same as,
D + 1 = E & 16 x 2 = 32.
E + 1 = F & 32 x 2 = 64.
Hence, the correct answer is option (b) E/32, F/64.