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: Prokaryotes are single-celled organisms that lack a nucleus., Fact2: Prokaryotes are usually microscopic and bacteria is an example of a prokaryote., Question: What are single celled organisms that do not have a nucleus? (A) Most plants (B) nucleus (C) ferns (D) fossil fuels (E) bushes (F) Eukaryotes (G) leech (H) bacteria
[A]: H

[Q]: Fact1: Biodiversity increases the productivity and stability of ecosystems., Fact2: Ecotourism, on the other hand, can help to conserve biodiversity., Question: What increases the stability of ecosystems? (A) overpopulation (B) water consumption (C) loose soil (D) Quality of life (E) agriculture (F) deforestation (G) ecotourism (H) trees
[A]: G

[Q]: Fact1: Some parasites kill their host, but most do not., Fact2: Leeches are external parasites., Question: Some what will kill their host, while others won't? (A) barnacles (B) producers (C) scavengers (D) insects (E) cigarettes (F) fungi (G) plants (H) leeches
[A]:
H