In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").
Q: Fact1: seconds are used to measure time, Fact2: An accounting period is simply a period of time., Question: What is used to measure a period? (A) percents (B) seconds (C) rainfall (D) lamphreys (E) feet (F) pounds (G) distance (H) meters
A:
B