The correct pronoun is "El" because he is a boy and he is your cousin so you have to use "El"
Answer:
sobrina
Explanation:
La hija de mi hermana means my sister's daughter, which is your niece, which translates to sobrina.
Second choice -in your lap
Answer:
d. los
Explanation:
las would be if they were women,
lo would be if the subjet is just 1 male person
la would be if the subjet is just 1 female person