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]: ['1979', 'b', 't', '1101', '7953', '2451', '7539', '6833', 'u', '49']
[EX A]: b, t, u

[EX Q]: ['i', '1191', '5581', '2527', 'g', '9795', '519', 'u', '8389', '9793', 'k', '5733', '7125', '7835', 'j', '855', 'd', 'd', '6555', '3211', 'l', 'o', 'b', '523', 'x', 'j', '1707', '4161', '7171', 'h', 'h', 'm', 'h', '2443', 'e', '649', '951', 'n', 'h']
[EX A]: b, d, e, g, h, i, j, k, l, m, n, o, u, x

[EX Q]: ['3751', 'u', '9165', 's', '2635', '169', 't', '8969', 't', '5505', 'o', '8541', 'o', 'f', 't', 'y', 'z', '3887', 'g', 'n', '6365', '9367', '1319', '1959', 'c', '7273', 'f', '2759', '4783', '9225', '5805']
[EX A]:
c, f, g, n, o, s, t, u, y, z