AMC 10B 2018 Problem 8

Sara makes a staircase out of toothpicks as shown:

This is a 3 -step staircase and uses 18 toothpicks. How many steps would be in a staircase that used 180 toothpicks?

Answer Choices
A. 10
B. 11
C. 12
D. 24
E. 30