Read the sentence and choices, and then select the choice with the correct words to complete the sentence. –Hola, Arturo, ¿tienes dos perros?
–Sí, los perros son Chewy y Nico.
–¿Cómo son los perros?
–Ellos son y .

Explanation:

Hola, Arturo, ¿tienes dos perros?

o

corras is the only one that is informal but doesn't follow the suffix rule. correr is the verb. corre is the formal verb form. corra would be used as the formal is corre ended with an a.

your best bet would be corras, it's the only one that is informal but is still wrong