Answer: the answer is 21
Step-by-step explanation:
Rly, this is the stupidest question to live on earth
The answer is B) -x^2-3
This is because you have an exponential graph that is flipped, hence the negative sign, and down 3.
I'm assuming this is multiple choice and you forgot to post the answers. I'll take a guess and say it probably looks something like this:

Because you can't take the square root of a negative number without getting an imaginary result, resulting in the function having a closed domain limit.