In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

[EX Q]: ['459', '1729', 'b', 'c', '9619', '4461', '4347', '6733', 'i', '3631', 's', 'j', 'i', 'r', '5293', 'q', '7397', '4309', 'c', 'n', 'k', '197', 'q', '8139']
[EX A]: b, c, i, j, k, n, q, r, s

[EX Q]: ['9579', 'm', 'v', 'r']
[EX A]: m, r, v

[EX Q]: ['u', '5531', 'k', '403', 'd', '1151', '9191', 'i', '6563', 'x', 'x', '3569', 's', '9281', '1931', 'v', 'r']
[EX A]:
d, i, k, r, s, u, v, x