Question

When it ______ research into heart disease and its effects on the body, we do not have adequate substitutes for the use of animals.

A．refers to

B．related to

C．comes to

D．talks to

Answer 1

C

考查句型：when it comes to 当谈到什么的时候，当谈到研究心脏病以及心脏病对人体影响的时候，我们没有足够的替代品在动物身上使用。故选C。