The correct answer is: [D]: "Este" . _______________________________________________ "ni<span>ño" is a single, masculine noun; as such, "Este" is the correct answer choice. _______________________________________________</span>
The correct demonstrative adjective for this sentences would be "este". * Este niño en la foto es mi primo Francisco". Because "ESTE" refers to a singular male subject. If it would have been a girl, the correct option would have been "ESTA". For plurals we need to use "estos" and "esa" when it is a singular, female and we point the subject at a certain distance. "Esa es mi prima" --> That is my cousin (over there)