Given the task definition and input, reply with output. 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").

Fact1: the looseness of soil increases the amount of oxygen in that soil, Fact2: Oxygen in the soil is vital for healthy roots., Question: What in soil is vital for healthy roots? (A) looseness (B) nutrients (C) leftovers (D) compacted (E) ferns (F) cells (G) energy (H) trash
A