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").

[Q]: Fact1: a delta is formed by deposition of sediment at the mouth of a river by water fanning out, Fact2: Rivers provide a water supply., Question: What is formed by deposition of sediment at the mouth of a water supply fanning out? (A) a hurricane (B) soils (C) a delta (D) an ocean (E) soft soil (F) an island (G) detritus (H) spring
[A]: C


[Q]: Fact1: Mollusks reproduce sexually., Fact2: Mollusks are the dominant invertebrate., Question: what reproduces sexually? (A) A compound that donates proton (B) spread flower seeds (C) They have webbed feet (D) Plant reproduction (E) By wind and rain (F) passenger pigeons (G) the dominant invertebrate (H) Something found in San Francisco
[A]: G


[Q]: Fact1: Echinoderms lack respiratory and excretory systems., Fact2: All echinoderms are marine and benthic., Question: what creatures lack respiratory and excretory systems? (A) Plant growth is reduced (B) marine and benthic (C) barnacles (D) epidermis and dermis (E) They may not survive. (F) kalenchoes (G) graptolites (H) movement of tectonic plates
[A]:
B