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)
Drink es el correcto verbo para beber.
Can’t really help, because there is a dialogue that you have to read in order to answer the questions
Answer: Do you just want me to translate it? It'd be "I have some red pens."
Explanation: