Answer:
Option fourth is correct that is the given algebraic expression is a polynomial
Explanation:
Monomial is that algebraic expression which contains one term
Binomial is that algebraic expression which contains two terms
Trinomial is that algebraic expression which contains three terms
And polynomial is the algebraic expressions that contains many terms
Hence, according to the definition the given algebraic expression [tex]7x^3+2x^2-9x+1[/tex] contains four terms hence it is a polynomial
Therefore,Option fourth is correct that is the given algebraic expression is a polynomial
