Silicon is the second most abundant element in Earth’s crust. It is used in the electronics industry to manufacture transistors, and in the construction industry to produce concrete and Portland cement. The following graph shows the relative abundances of the naturally occurring silicon isotopes.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.

i belive it is water