The correct active form of the given sentence is All my friends trust me.

The sentence "I am trusted by all my friends" is in the passive voice. The passive voice 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 "I" and the main verb is "trust." The past participle of "trust" is "trusted." So, the passive form of the sentence is "I am trusted by all my friends."

The active voice is formed by putting the subject of the passive sentence before the verb and the past participle of the main verb. In this case, the subject of the passive sentence is "all my friends" and the main verb is "trust." The past participle of "trust" is "trusted." So, the active form of the sentence is All my friends trust me.

The other options are incorrect because:

• I trust all my friends is the passive form of the sentence.
• I have trusted all my friends is in the present perfect tense, while the original sentence is in the simple present tense.
• All my friends trusted me is in the past tense, while the original sentence is in the simple present tense.