Plants . . . . . . by the gardener, see. A. are being watered B. are watering C. are being watering D. are watered

The correct answer is: Plants are being watered by the gardener.

The verb “water” can be used in two different ways:

• Intransitively, to mean “to pour water on something.”
• Transitively, to mean “to provide water for something.”

In this sentence, the verb “water” is being used transitively. The gardener is providing water for the plants. Therefore, the correct answer is “are being watered.”

The other options are incorrect because they do not agree with the tense of the sentence. The sentence is in the present progressive tense, so the verb must also be in the present progressive tense.

• Option A: “Plants are watering” is incorrect because it is in the present tense.
• Option B: “Plants are being watering” is incorrect because it is in the present passive voice.
• Option D: “Plants are watered” is incorrect because it is in the simple past tense.