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").
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Question: Fact1: Male dogs use pheromones in urine to mark their territory., Fact2: Pheromones are natural aphrodisiacs., Question: What do male dogs use in urine to mark their territory? (A) Natural aphrodisiacs (B) competing for resources (C) Tails (D) Urine  cleaner (E) Something coming from a gland (F) Chemical energy (G) an area swollen with pus (H) Chew toys

Answer: A


Question: Fact1: a light bulb is used for seeing in the dark, Fact2: Conventional light bulbs generate light by heating a filament., Question: What is helpful for seeing in the dark? (A) an electron microscope (B) an electron lens (C) microscope (D) closing the blinds (E) blackouts (F) closing your eyes (G) focusing a lens (H) heating a filament

Answer: H


Question: Fact1: evaporation can be used for separating a solute from a solvent in a solution, Fact2: An aqueous solution has water as the solvent., Question: Evaporation can be used for separating a solute from a water in what? (A) molecule (B) Condensation (C) atom (D) aqueous solution (E) Heat energy (F) vaporization (G) evaporation (H) aqueous chemical

Answer:
D