Correct answers only ! elige la respuesta correcta. ¿quién es el hijo de mis padres?

The correct answer is:   [C]:

             →   " mi hermano " .

Note:  The question reads as:

Choose the correct answer.

  "Who is the son of my parents? " ;

          →    {followed by 4 (four) answer choices}.

Choice [A]: " mi madre" ;  which means:  "my mother" ; does not make sense.  {Note:  "my mother" ; cannot be someone's correct response to:  "Who is the son of my parents?" ;  since:  "My mother" (female) cannot be anyone's "son" (being female); and one's "mother" is one's parent and cannot be the "son or daughter" of one's parent(s).

   →  Choice [A]:  is incorrect.

Choice [B]:  " mi suegra" ;  which means: "my mother-in-law" .

See reasons above {for why "Choice [A]" is incorrect.}."

  →  Choice [B]:  is incorrect.

Choice:  [C]: " mi hermano " ; which means:  "my brother" .

 Note:  "Who is the son of my parents?"  If one were asked this question; one could sensibly and logically respond with this answer choice [if one did, in fact, actually, have a brother; since one's  "brother" would, in fact, be share one's  same parents!] .

Choice:  [D]:  " mi abuelo " ;  which means:  "my grandfather" .

   Note:  "Who is the son of my parents?"  If one were asked this question, one could Not sensibly — or logically — respond with:  "my grandfather".

It is possible to have 2 (two) living grandfathers; yet neither of the grandfathers would be the "son" of one's parents.  To the contrary, each of them would be the father of [one of the one's 2 (two) parents.].

  →  Choice [B]:  is incorrect.

So;

The correct answer is:   [C]:   " mi hermano " .

Hope this helps!

    Best wishes to you in your academic pursuits

              — and within the community!