C. Reciben, because ninos is plural so the answer is reciben.
I think you mean conjugation, but anyhow it depends on how you are using it..
There are some rules, but the pronunciation is also important.
If the word ends in a vowel, an “n”, or an “s”, stress the last-but-one syllable:
If the word ends in a consonant other than “n” or “s”, stress the last syllable: ...
If the word has an acute accent, ignore the above rules and stress the accented syllable:
<span>The volcano with the enormous crater found just north of Alajuela is</span> el Volcán Poás.
