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

"Whom did you see at the shopping mall today?” I asked my daughter.

I asked my daughter whom she had seen at the shopping mall that day.

The correct option is:

I asked my daughter whom she had seen at the shopping mall that day.

The other options are incorrect because they do not follow these rules:

• I asked my daughter who she has seen at the shopping mall today. - This sentence does not change the present tense to the past tense for the auxiliary verb "did."
• I asked my daughter that whom she saw at the shopping mall on that day. - This sentence does not change the question word order so that it comes before the subject.
• I asked my daughter that whom did she saw at the shopping mall that day. - This sentence is grammatically incorrect.