Concept:In active voice, the subject performs the action. In passive voice, the subject receives the action.
Explanation:Check each sentence for the verb form.
Option A: "will be caught" – uses "be + past participle" (passive voice).
Option B: "I know" – subject "I" performs the action of knowing. It is simple present active.
Option C: "is not taught" – "is + past participle" (passive voice).
Option D: "was knocked" – "was + past participle" (passive voice).
Only option B has the subject doing the action directly. Hence, it is active voice.
For reference, below is a table showing active and passive verb forms across tenses:
Answer:Option B: "I know nothing about western philosophy." is the correct active voice sentence.