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]: ['565', 'i', '615', '3047', 'm', '195', '7547', '3003', '9213', '9063', 'c', '5099', 'v', '5003', '9053']
[EX A]: c, i, m, v

[EX Q]: ['2521', '8027', 'm', '193', '615', 'l', '1947', '5949', '6307', 'r', '1015', '743', 'v', '6949', 'b', 'g', '8841', 'c', 'b', '2879']
[EX A]: b, c, g, l, m, r, v

[EX Q]: ['327', '8551', '993', 'x', 'i', '669', 'h', '5615', '6329', '8633', '763', '4573', 't', '8073', '1107', 's', 'v', 'g', 'k', 'r', 'h', '8721', '2529', 'o', 'y', 't', 'u', 'q', '3829', '3203', '7031', 'i', '9467', '8331']
[EX A]:
g, h, i, k, o, q, r, s, t, u, v, x, y