Select the correct passive form of the given sentence.

The commander ordered his soldiers to move forward and attack the enemy camps.

The soldiers were ordered by their commander to move forward and attack the enemy camps.

The correct passive form of the given sentence is The soldiers were ordered by their commander to move forward and attack the enemy camps.

The active voice of the sentence is The commander ordered his soldiers to move forward and attack the enemy camps. This sentence is in the simple past tense, which is used to describe an action that happened in the past. The passive voice of the sentence 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 "the soldiers" and the main verb is "order." The past participle of "order" is "ordered." So, the passive form of the sentence is The soldiers were ordered by their commander to move forward and attack the enemy camps.

The other options are incorrect because:

• The commander ordered his soldiers to be moved forward and attacked the enemy camps. is grammatically incorrect. The verb "to be" should not be used with the gerund "moving."
• His soldiers were ordered by the commander to be moved forward and attacked the enemy camps. is grammatically incorrect. The possessive pronoun "his" should not be used with the subject "soldiers."
• The commander was ordered by his soldiers to move forward and attack the enemy camps. is grammatically incorrect. The subject of the sentence is "the commander," which is singular. The verb "were" is plural.