Open the brackets and choose the correct verb form - Past Perfect or Past Perfect Continuous. My brother __ (try) to repair the TV for two hours before I called him. a. had been trying b. had tried c. tried

The correct answer is a. had been trying.<br /><br />The sentence is describing an action that was ongoing in the past before another event occurred. The Past Perfect Continuous tense is used to express this type of action. In this case, the action of trying to repair the TV was ongoing for two hours before the speaker called their brother. Therefore, the correct verb form is "had been trying."