Answer:
and 
Step-by-step explanation:
An algebraic expression is a polynomial if and only if the variables involve have positive integral indices or exponents.
The given polynomial is: 
We want to put one of the following polynomials in the blank space to create a fully simplified polynomial written in standard form.





A fully simplified polynomial written in standard form is obtained by writing the simplified polynomial in decreasing order according to degree.
Since the first term of
having a degree of 5 and the last term is having a degree of 3.
The polynomial that goes into the blank must have a degree of 4.
This eliminates
, 
and 
We are now left with
and 
The required polynomial is therefore
or
These two polynomials are in standard form and cannot be simplified further.
The correct choices are;
and 