Select the option that expresses the given sentence in reported speech.

He said to his sister, “Please help me with my homework.”

He requested his sister to help him with his homework.

The correct option is:

He requested his sister to help him with his homework.

The other options are incorrect:

• His sister told him that he should help her with her homework. This is incorrect because the speaker is talking about himself, not his sister.
• His sister was asked by her brother that she should help him with his homework. This is incorrect because the reporting verb is "was asked", which is used for indirect speech when someone is being asked something.
• He told his sister that she should help him with his homework. This is incorrect because the speaker is making a request, not a statement.