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").

Example input: Fact1: a plant requires sunlight to grow, Fact2: Plants to avoid are fast-growing vines that can take over an area in no time., Question: What requires sunlight in order to take over an area? (A) spores (B) fish (C) plants (D) humans (E) pods (F) Oak (G) opossums (H) coral
Example output: C
Example explanation: This is a good example. Based on the facts plants require sunlight in order to take over an area.
Q: Fact1: All life relies on a relatively narrow range of pH, or acidity., Fact2: All organisms have a life-span., Question: Organisms rely on a relatively narrow range of what? (A) Decibels (B) water (C) food (D) relativity (E) acidity (F) spectrum (G) balance (H) Light
A:
E