Problem: If "The dog chased the cat, which ran up a tree. It waited at the top.", is "The dog waited at the top." correct?

Answer: no


Problem: If "Anna did a lot worse than her good friend Lucy on the test because she had studied so hard.", is "Lucy had studied so hard." correct?

Answer: yes


Problem: If "Sam broke both his ankles and he's walking with crutches. But a month or so from now they should be unnecessary.", is "The ankles should be unnecessary." correct?

Answer:
no