Answer:
Option A
Explanation:
$Z - 6 \rightarrow T, T - 6 \rightarrow N, N - 6 \rightarrow H, H - 6 \rightarrow B $
$Z - 3 \rightarrow W, W - 3 \rightarrow T, T - 3 \rightarrow Q, Q - 3\rightarrow N,$
$ N - 3\rightarrow K, K - 3\rightarrow H - 3 \rightarrow E, E - 3\rightarrow B$
Hence the answer is (a).