ANSWER:
A. 1
STEP-BY-STEP EXPLANATION:
A linear function is a polynomial function of the first degree, that is, a function of a variable, which can be written as follows:
[tex]y=mx+b[/tex]
Therefore, the correct answer would be:
[tex]\begin{gathered} y=x^1-31 \\ y=x-31 \end{gathered}[/tex]
