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]: ['2527', '9123', '8717']
[EX A]: -1

[EX Q]: ['c', '8785', 'u', 'i', 'i', '6513', '6093', 'w', 'i', 'x', '9377', 'p', '1545', '7997', 'a', 'c', '125', 'u', '9149', '9103', 'u', 'o', 'h', '2275', '8503', '3251', 'c', '9925', 'w', '6873', 'c', 'h', 'e', '2369', 'c', 'z', '1337', '9541', '675', 's']
[EX A]: a, c, e, h, i, o, p, s, u, w, x, z

[EX Q]: ['n', '6629', '877', '5581', '4035', '6541', '369', '7959', '5345', '1293', 'q', 'w', 'i', 'r', 'c', 'u', '3333', 's', 'k', '7299', 'x', '5551', '103', 'm', 'y', 'g', '6411', 'g', '5491', '3083', 'y', 's', 'u', 'h', '7657', '3309', 'h', 's', '2315', '1907', 'o', 'x', '8197']
[EX A]:
c, g, h, i, k, m, n, o, q, r, s, u, w, x, y