Select the option that expresses the given sentence in active voice.

Where was this pen found by him?

Where did he find this pen?

The correct active voice form of the given sentence "Where was this pen found by him?" is Where did he find this pen?

The passive voice of the sentence is "Where was this pen found by him?" This sentence is in the interrogative form, which is used to ask a question. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "he" and the main verb is "find." The past participle of "find" is "found." So, the passive form of the sentence is "Where was this pen found by him?"

The active voice of the sentence is formed by putting the subject of the passive sentence before the verb and removing the word "by." In this case, the subject of the passive sentence is "he," and the verb is "find." So, the active form of the sentence is "Where did he find this pen?"

The other options are incorrect because:

• Where do he find this pen?" This sentence is in the present tense, but the action of finding the pen happened in the past.
• Where does he find this pen?" This sentence uses the wrong form of the verb "find." The correct form is "find."
• Where did he found this pen?" This sentence uses the wrong form of the past participle of the verb "find." The correct form is "found."