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]: ['1801', 'q', '5101', '8863', '2309', 'p', '8789', '9529', '6135', '5523', 'f', '8889', '7639', 'k', '263', '5751', '5529', 'g', '1451', '4143', 'e', '6987']
[EX A]: e, f, g, k, p, q

[EX Q]: ['5761', '2289', '577', 't', '125', 'i', 'g', '9693', '747', 'd', '4829', '9587', 'f', 'k', 'w', 'v', '8607']
[EX A]: d, f, g, i, k, t, v, w

[EX Q]: ['353', 'r', 'l', 'f', '4181', '6469', '6581', 'z', '4199', 'd', '3217', '6231', 'f', 'w', '2709', '173', 'u', 't', '2779', 'o', '9209', '8301', 'x', '9231', '8303']
[EX A]:
d, f, l, o, r, t, u, w, x, z