Sara: no sé lo que me pasa, la verdad. estoy
david: creo que demasiado. ¿has ido al
sara: no he ido porque no tenía ,sólo era un ligero
david: deja de ser una niña. tienes que
sara: por eso te llamo. no se me va el dolor de estómago ni con
david: ahora mismo llamo al doctor perales para hacerle una

Sara: No sé lo que me pasa, la verdad. Estoy siempre agotada.

David: Creo que estás adelagazando demasiado. ¿Has ido al médico?

Sara: No he ido porque no tenía fiebre ,sólo era un ligero malestar.

David: Deja de ser una niña. Tienes que ponerte bien.

Sara: Por eso te llamo. No se me va el dolor de estómago ni con pastillas.

David: Ahora mismo llamo al doctor Perales para hacerle una consulta.

Explanation:

The word "agotada" translates to "tired" and refers to a feminine pronoun. Sara speaks about herself on the first line of dialogue and, so this is the correct word  as she expresses concern about her condition.

On the second line, David first tries to give a reason to explain Sara's discomfort, using the phrase "estás adelagazando demasiado" which translates to "you (Sara) are losing too much weight". Afterwards he would ask Sara if she has seen a doctor. The spanish word for doctor is "médico".

Sara says that she hasn't, because she didn't suffer from any severe symptoms. One of those symptoms could be "fiebre" which means "fever". She'd only had a slight discomfort, that is "un ligero malestar".

David then tells Sara to stop kidding, because he wants her condition to improve. He wants her to get better, which he expresses as "(tú, Sara) tienes que ponerte bien".

After that, Sara tells David that nothing has relieved her from her stomachache. In the options, the word "pastillas" refers to pills, which Sara may have taken during her illness. Sara  asks David for help.

Finally, David says he will call a doctor to ask him about it. Here we use the word "consulta" because the phrase "hacer una consulta" refers to asking information about something in particular.