If \(\log_5(\log_8(x^2 - 1)) = 0\), then a possible value of \(x\) is

A log equal to 0 means its argument is 1, so log base 8 of (x squared - 1) = 1. Hence x squared - 1 = 8, x squared = 9 and x = 3 or -3; only 3 is offered. Trying 2 root 2 gives x squared - 1 = 7, which does not make the base-8 log equal to 1.