[Q]: How does the sentence end?

Katrina had a torso that was twice as wide as that of Betty because

[A]: Katrina was rather overweight.

[Q]: How does the sentence end?

Choosing paint was easier for Emily than Mary because

[A]: Mary had a weak knowledge of color theory.

[Q]: How does the sentence end?

Ian received a turtle from Michael for their birthday so

[A]:
Michael also got them a cage for it.