Answer:
C
Explanation:
The answer is C because estudiantes means students and students are a plural word. Furthermore, you use the word "an" as the conjugation when something is plural. Therefore, the best conjugation that represents that is guardan.
Here are all the conjugations of a present tense word in Spanish: I will use the example comprar.
Compro = I buy
Compras = You buy
Compra = He/she buy
Compramos = We buy
Compran = They buy
So basically if something ends with something, it represents a unique pronoun for that verb.
Ending with o = I
Ending with as = You
Ending with a = He/she
Ending with amos = We
Ending with an = They
