Match the lack of clear pronoun reference to the correct lack of

clear pronoun reference solution: A pronoun reference that is weak or
vague
Solutions:
a. Rewrite the sentence, eliminating the pronoun entirely, or
rewrite the sentence, substituting a noun for the pronoun.
b. Rewrite the sentence, substituting a noun for the pronoun, or
rewrite the sentence, making the antecedent of the pronoun
clear.
c. Rewrite the sentence, adding a clear antecedent for the
pronoun, rewrite the sentence, substituting a noun for the
pronoun.

Lack of clear pronoun reference solution: b. Rewrite the sentence, substituting a noun for the pronoun, or rewrite the sentence, making the antecedent of the pronoun clear.