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: Some viruses have an envelope of phospholipids and proteins., Fact2: Intrinsic proteins are embedded in the phospholipid., Question: Name one kind of a protein that some viruses have inside their phospholid envelope? (A) layers of fat (B) more abundant (C) positive (D) negative (E) allow growth (F) Leptospirosis (G) intrinsic (H) bioaerosols
G