ALGUNAS V ALGUNA

Question

I don't understand why my answer to No 1 was incorrect: "... fotografias. Queres ver algunas?"I chose "algunas"because it agreed in gender and number with fotografias and was not in the affirmative. Very confusing.

Accepted Answer

Hola Jacqui
There is special attention in the lesson about his usage of alguno/alguna in singular, when we have a plural referent in the English. The hint is saying in this specific question "choose the correct singular option", so "algunas" is incorrect. 
If you go back to the lesson, you will read that sometimes we use it in the singular to refer to "the odd one" "one or two" ... 
This is the case in this quiz.
Saludos
Inma

Answer

the reason is because it is referring to ´any´ and that is a quantity of one. Hope that makes sense!