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]: ['7917', '2295', 'q', 'v', '9373', 'w', 'n', 'q', '5803', 'g', 'k', 'm', '2167', 'k', '6425', 'x', 'g', '341', 't', 'u', '8829', 'h', '4333']
[EX A]: g, h, k, m, n, q, t, u, v, w, x

[EX Q]: ['k', 'c', 'i']
[EX A]: c, i, k

[EX Q]: ['k', 'l', 'c', 'v', 'z', 'l', 'v', 'p', '7759', '5747', 'y', '8919', 'u', 'q', 'c', 'n', 'c', '6469', 'd', 'c']
[EX A]:
c, d, k, l, n, p, q, u, v, y, z