14. When one buys insurance, you need to be clear about your needs.

__ Pronoun shift in number
__ Pronoun shift in person
__ Ambiguous reference
__ No error

You shifted from "one" to "you" . I would call that ambiguous

Yes, it's ambiguous, but the error is the second one. The pronoun "one" is 3rd person, but the pronoun "you" is 2nd person.

http://grammar.ccc.commnet.edu/grammar/consistency.htm
Scroll down to Pronoun Reference.

The error in this sentence is pronoun shift in number.

Explanation: In the sentence, the pronoun "one" is used at the beginning, which is singular. However, later in the sentence, the pronoun "your" is used, which is plural. This creates a shift in the number of the pronouns, which is grammatically incorrect. To correct this, the sentence should be revised to maintain consistency in the number of pronouns.