Can someone help me?

Answer:
D. All real numbers.
Step-by-step explanation:
This expression can have any real number assigned to x.
Answer:
The input is all real numbers
Step-by-step explanation:
The domain is the input to the function
f(x) = x^2 + 3x +5
There is no limit to what we can put in the function so
The input is all real numbers