d is the answer, because the decimal for (pi) is never terminated and any repetition is purely fortuitous and there is no repeating pattern. (Answer a is insufficient because many decimals don't repeat but they do terminate; b is incomplete because a recurring decimal doesn't terminate, but it does repeat; c doesn't apply, because (pi) does not repeat like a recurring decimal, for example, 22/7 is an approximation for (pi) and it is a repeating decimal, but it's only an approximation.)