In the case of Interrogative sentences like this, "said" in Direct Speech is changed into "enquired (of)", "wanted to know", "asked", etc.
In Indirect speech, the verb is always placed after the subject, unlike in Direct Speech.
If there is a question in the Direct Speech whose answer can come as "Yes" or "No" in the Indirect Speech, we should use the conjunctions "if" or "whether".
For example:
Ravi said to me, "Is she studying?" (Direct Speech)
Ravi asked me if she was studying. (Indirect Speech)
Also, the sentence in the Direct Speech is in the Present continuous tense. So, the tense in the Indirect Speech should be in the Past continuous tense.
The following things in the sentence should change when changed from Direct speech to Indirect Speech:
'If' will be introduced in the sentence.
'Are you' will be changed to 'we were'.
'My' will be changed to 'her'.
'Next week' will be changed to 'following week'.
Therefore, the correct answer is option (c): She asked if we were meeting her partners the following week.