Please help, Im confused with linear graphing

Answer:
C.
Step-by-step explanation:
I learned this years ago, but I think it's answer C. Because the others (curved lines) would be classified as Non-linear.
*(( I sincerely apologise if this turns out to be the wrong answer. Lol))
Answer:
C
Step-by-step explanation:
When you see the word "linear," think "line." Only one of the four given graphs is a straight line: C