I DONT KNOW WHAT THE ANSWER IS REALLY
Option C: 
The last two terms given of the standard polynomial are:

This shows 2 patterns to us:
r 's degree is increasing per term in the given polynomial.
s 's degree is decreasing per term in the given polynomial.
The sum of powers of variates r and s is 2+4 = 3+3 = 6.
And since standard polynomial, the same pattern must be present in all terms of the series.
All options except C are not valid.
Option C has term
for which r's degree plus s's degree is 1 + 5 = 6.
And r's degree 1 < s's degree 5.
Thus its a valid term to be putted as first term in standard form of polynomial in consideration.
Thus Option C:
is the needed expression.
Learn more here:
brainly.com/question/10127580
<span>A matrix is basically a table of columns and rows.
One way to use an array is to tabulate information concerning two variables, for example, sizes of shoes and person's height, or price of different kinds of vegetables over 12 months, etc.
So for your problem, think of two variables that you can tabulate in your sports team. If you are out of ideas, read the sports page.</span>
5th grade. ( my little sister)