Choose the correct passive voice: The chef prepares delicious meals.

The correct answer is A: Delicious meals are prepared by the chef. To transform an active voice sentence into the passive voice, several steps are followed. First, the object of the active sentence ('delicious meals') becomes the subject of the passive sentence. Second, the verb form changes to 'be' + the past participle of the main verb. Since the original sentence 'The chef prepares delicious meals' is in the simple present tense, and the new subject 'delicious meals' is plural, the correct form of 'be' is 'are', and the past participle of 'prepares' is 'prepared'. Finally, the original subject ('the chef') can be included as an agent, introduced by 'by'. Options B, C, and D are incorrect because they either use the wrong tense ('were prepared'), incorrect subject-verb agreement ('is prepared'), or do not correctly form the passive voice ('prepare').