How would you tell a group of people to go to the bank?
a. vayan al banco.
b. van al banco* i think
c. vaya al banco
d. vais al banco

how would you tell someone older than you not to be mad?
a. no es malo
b. sean no malo
c. no sea malo
d. no son malo

Part 1:
-Vayan al banco, nice, not commanding. "Y'all go to the bank = Vayan al banco"

-Van al banco is more of asking a question. "Are y'all going to the bank? = ¿Van al banco?"

-Vaya al banco is commanding. "Go to the bank. = Vaya al banco"

-Vais al banco is not proper Spanish at all.

So the answer would be A) Vayan al banco.

Part 2:
Malo is bad, did you mean Enojado, which means mad? We'll go with Malo.
-No es malo is more of a question. "You're not mad? = ¿No es malo?"

-Sean no malo, not, not, not proper Spanish.

-No sea malo, is a question, BUT it is asking not to be mad. "Don't be mad = No sea malo."

-No son malo, this is a statement. "They're not mad = No son malo"

Therefore, the answer would be C) No sea malo.

Hope this helps!~