The sum of two polynomial functions will also be a polynomial function. The exponents of the variables in the polynomial function are non-negative integers. Option A is an exponential function. Option B is a logarithmic function.
The formatting is not proper in the options C and D. Only 1 option can be the correct answer.
If the options are:
Then option C would be the correct answer as in option D variable is in the exponent which is against the definition of polynomial function.
If the options are:
Then option D would be the correct answer as in option C variable is in the exponent which is against the definition of polynomial function.