Which of the following contains a vague pronoun reference?
A: The Chens' car has a dent in the bumper, but otherwise their car looks just like the Duncans'.
B: The Chens' car looks just like the Duncans', but theirs has a dent in the bumper.
The first answer choice contains a vague pronoun reference. The pronoun theirs could refer to the Chens' or the Duncans'.
The Chens' car looks just like the Duncans', but theirs has a dent in the bumper.
The second answer choice shows a possible correction for the vague pronoun reference. The text has been rewritten so that the meaning is clear.
The Chens' car has a dent in the bumper, but otherwise their car looks just like the Duncans'.