Answer the following question: Fact 1: Chemical weathering causes iron in rock to oxidize. Fact 2: Rust colored residues are due to oxidized iron. Given the two facts above, what causes rust?

OPTIONS:
[A]. a pathogens
[B]. Roundworms
[C]. flow of electrons
[D]. dust
[E]. thunder
[F]. an amoebae
[G]. chemical weathering
[H]. skin
Answer:
[G].