Answer :
A Past Perfect Tense indicates actions that have been accomplished or done in the past before another action takes place. In the choices given, the example of the sentence that uses past perfect tense is, "Carl had asked his mother's permission before he left town."
The past perfect tense indicates that an action was completed at some point in the past before something else happened.
Subject+had+past participle=past perfect tense.
Therefore, the sentence that uses the past perfect tense is, "Carl had asked his mother's permission before he left town."