Select the correct direct form of the given sentence.

Mother ordered the children to stop playing then.

Mother said to the children, “Stop playing now.”

The correct direct form of the sentence "Mother ordered the children to stop playing then" is Mother said to the children, "Stop playing now."

The other options are incorrect:

• Mother said to the children, "Don't play then." This is incorrect because the tense of the reported speech should be "now" instead of "then."
• Mother said to the children, "Please stop playing then." This is incorrect because the tense of the reported speech should be "now" instead of "then."
• Mother said to the children, "Can you stop playing now?" This is incorrect because the reporting verb "ordered" indicates that Mother was giving a direct command, not asking a question.