B. During the visit to the zoo, i noticed fewer animals sleeping
The sentence has a vague pronoun problem because it is unclear if the police officer or the criminal tripped and fell. In order to correct this, the sentence needs to be more specific. We can say any of the following sentences:
The police officer chased the criminal through the streets until <u>the officer </u>tripped and fell.
- It is clear that the officer fell.
The police officer chased the criminal through the streets until <u>the criminal </u>tripped and fell.
- It is clear the criminal fell.
This sentence wouldn't necessarily work with the original sentence since we can infer that only one of them fell because the writer used he. However, if both of them fell, it would be correct as well.
The police officer chased the criminal through the streets until <u>they</u> tripped and fell.
