Which polynomial is in standard form

Last option is correct.

Step-by-step explanation:

We are given with some polynomials.

We have to tell which one is in standard form of polynomial.

In Standard Form of a polynomial , Terms are arranged in decreasing or descending order of degree of the terms.

Polynomial 1.

1 + 2x - 8x² + 6x³

In this Terms are arranged in Increasing order of degree of terms.

This is not in Standard form.

Polynomial 2.

2x² + 6x³ - 9x + 12

In this polynomial first two terms are arranged in Increasing order of degree while last two arranged in decreasing order of degree.

This is not in Standard form.

Polynomial 3.

6x³ + 5x - 3x² + 2

In this Terms are arranged in jumbled order of degree

This is not in Standard form.

Polynomial 4.

2x³ + 4x² - 7x + 5

In this Terms are arranged in Decreasing order of degree of terms.

This is in Standard form.

Therefore, Last option is correct.