In this task, you are given inputs 'i', 'j', and A, where 'i' and 'j' are integers and A is a list. A list is shown by two brackets and comma-separated numbers and characters inside, like ['1', '12', 'l']. You need to concatenate all elements of A from the ith element to the jth element, and then reverse the resulting string. 'i' and 'j' will be non-negative, and will always have a value less than the length of A. 'i' will always be less than 'j'. Perform the operations in order, i.e., do not reverse first and then concatenate.
8, 21, ['7121', '3405', 'B', 'h', 'l', 'G', 'M', 'n', 'X', 'r', 'X', 'X', 'o', '7601', 'P', 'o', 'S', 'B', 'n', '8663', '1585', '9565', 'V', 'R', 'Y', '9673']