Mrs. Allard asked her students to identify which of the polynomials below are in standard form and explain why.

1.
15x
- 6x + 3x² - 1
II.
12x + 8x + 4
III.
2x + 8x + 10x

Which student's response is correct?
1) Tyler said I and II because the coefficients are decreasing.
2) Susan said only II because all the numbers are decreasing.
3) Fred said II and III because the exponents are decreasing.
4)
Alyssa said II and III because they each have three terms.