Select the option that expresses the given sentence in passive voice.

The clouds hid the sun.

The sun was hidden by the clouds.

The correct option that expresses the given sentence in passive voice is The sun was hidden by the clouds.

The other options are incorrect because:

• The sun is hidden by the clouds uses the present tense, while the original sentence is in the simple past tense.
• The clouds are hid by the sun is grammatically incorrect. The verb "hid" is in the past tense, but it is not used correctly in the passive voice.
• The sun was hide by the clouds is grammatically incorrect. The verb "hide" is in the infinitive form, but it is not used correctly in the passive voice.