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: Many corals secrete an exoskeleton that builds up to become a coral reef., Fact2: Good examples are Bubble coral, Elegance coral, Frogspawn and other Euphyllia corals., Question: What is secreted by organisms like frogspawn to become a reef? (A) exocrine glands (B) food and shelter (C) exoskeleton (D) bones (E) Energy (F) Chemical energy (G) plasma (H) Energy.
C

Fact1: satellites are used to take images from space, Fact2: Satellite images are digital photographs., Question: Satellites are used to take what from space? (A) rapid changes occur (B) snow, ice, and rock (C) trees and flowers (D) painters (E) occurs over a wide range (F) digital photographs (G) digital files (H) photographers
F

Fact1: Biodiversity increases the productivity and stability of ecosystems., Fact2: Oceans are one of the largest ecosystems in the world., Question: Biodiversity increases the productivity and stability of what? (A) ferns (B) fungi (C) animals (D) bushes (E) trees (F) wetland (G) oceans (H) plants

G