If mass is conserved during a nuclear reaction, then the mass of the daughter elements will have decreased from that of the parent element the total atomic mass of the daughter elements should equal that of the parent element the mass of the daughter elements will have increased by as many protons as times decayed from the parent element the mass of the parent elements will have split evenly into two identical daughter elements

the answer to your question is c.

if you read the house of usher you should know that the house was haunted

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.