What is the slow, rate-determining step, in the acid-catalyzed dehydration of 2-methyl-2-propanol?

H2SO4
(CH3)3COH →

a. Protonation of the alcohol to form an oxonium ion.
b. Loss of water from the oxonium ion to form a carbocation.
c. Loss of a β-hydrogen from the carbocation to form an alkene.
d. The simultaneous loss of a β-hydrogen and water from the oxonium ion.

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.