Answer:
B. The burgers were grilled and then topped with delicious, tangy blue cheese.
Step-by-step explanation:
Delicious and tangy are both adjectives meaning you need to separate them with a comma.
As for the other 2 options, deep and purple don't need to be separated because deep describes purple. Also, tiny describes electrical so you don't need it either. If they are separate adjectives with no similarity you need a comma.
I hope this helps!