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").

[EX Q]: Fact1: Some arthropods have special excretory structures., Fact2: All insects are arthropods., Question: what sometimes has special excretory structures? (A) insects (B) bees (C) a fish (D) barnacles (E) animals (F) carbon (G) feces (H) humans
[EX A]: A

[EX Q]: Fact1: an egg requires warmth to survive, Fact2: First the frog lays the eggs, then the warmth from the sun makes the eggs hatch into baby tadpoles., Question: what keeps eggs warm? (A) ice (B) hair (C) wool (D) bears (E) fur (F) sun (G) moss (H) sand
[EX A]: F

[EX Q]: Fact1: a delta is formed by deposition of sediment at the mouth of a river by water fanning out, Fact2: Deltas are usually fan-shaped deposits of sediment that form where currents slow at a river's mouth., Question: Fan-shaped deposits of sediment form where? (A) mouth of rivers (B) bottom of oceans (C) flooding (D) near the shoreline (E) the Great Barrier Reef (F) entrance of puddles (G) unidirectional (H) top of canyons
[EX A]:
A