Choose the option in which the following sentence has been changed into…

Correct passive sentence: I am sometimes vexed by his attitude.

Explanation:

• Identify parts in the active sentence: subject = his attitude, verb = vexes, object = me, adverb = sometimes.

• Make the object 'me' into the subject of the passive and use the correct form of 'be' + past participle: 'I am vexed'.

• Introduce the original subject as the agent with 'by': 'by his attitude'.

• Place the adverb 'sometimes' where it naturally fits. The final sentence is: 'I am sometimes vexed by his attitude.' (Alternatively, 'I am vexed by his attitude sometimes' is also acceptable.)