Righ answer: Sí, te llamaré
This is an interrogative sentence with the verb llamar (to call) in future with the 2nd person singular tú (you), although the subject tú is not explicitly here (because is a Tacit Subject).
By logic, if a question is done with the subject tú, the answer must be with the subject yo (I).
The conjugation of the verb llamar in future with the 1st person singular yo (I) is llamaré.
Hence, the answer to the question:
¿Me llamarás por la mañana?
Will you call me in the morning?
Is:
Sí, te llamaré
Yes, I will call you
The other options are incorrect because they do not agree with the subject of the answer:
Sí, me llamaré
Yes, I will call me
Sí, los llamaré
Yes, I will call them