The correct option is
B Ann asked Benny why she had gone to the hair dresser to which Benny replied that she wanted to have her hair cut.
The two ways of relating what a person has said are 1)direct and 2)indirect (reported speech).
In direct speech, the original speaker's exact words are repeated. Direct speech is found in plays and quotations.
In indirect/reported speech, the exact meaning is expressed but not necessarily using the original speaker's exact words.
Tenses, pronouns, and possessive adjectives, and adverbs of time and place change while reporting.
The introductory verb asked is used when a question and its reply is given, to which is used to connect the question and the reply, and the introductory verb replied is used while transforming a direct speech to the indirect speech.
When we change direct questions to indirect speech, the interrogative form of the verb changes to the affirmative form. The question mark (?) is therefore omitted in indirect questions.
The correct answer is option B as the above-mentioned rules are followed, the simple past tense in the question is changed to the past perfect tense, and the simple present in the sentence to the simple past tense.
The other options are wrong as the right tense and pronouns are not used.
The correct answer is B)Ann asked Benny why she had gone to the hair dresser to which Benny replied that she wanted to have her hair cut.