Final answer:
The sentence 'A talented young player in the National Football League can find themselves very wealthy in a short period of time' contains an error in pronoun-antecedent agreement because the antecedent is singular and the pronoun is plural.
Step-by-step explanation:
The correct answer is A) 'A talented young player in the National Football League can find themselves very wealthy in a short period of time.' This sentence contains an error in pronoun-antecedent agreement.
In English, the pronoun and its antecedent should agree in number. That means if the antecedent is singular, the pronoun also has to be singular. If the antecedent is plural, the pronoun also has to be plural.
In the sentence provided in option A, the antecedent 'A talented young player' is singular while the pronoun 'themselves' is plural. Hence, there is a mismatch in number which results in an error in pronoun-antecedent agreement.
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