Explanation : The first letter of each triplet follows a
sequence of A, C, E, G, I and so on. The second letter
of each triplet follows a sequence of B, D, F, H, J and so
on, and the third letter forms a sequence of D, F, H, J,
L and so on.
Explanation : The first letters form a series of C, D, E, F, G
and so on. The second letters form a series of K, L, M,
N, O and so on. The third letters form a series of Z, Y,
X, W, V and so on.
Explanation : The first letters form a series of N, O, P, Q, R
and so on. The second letters form a vowel series, and
the third letters form prime number series according to
their number position.