The steps below show the incomplete solution to find the value of m for the equation 4m − 2m + 4 = −1 + 13:

Step 1: 4m − 2m + 4 = −1 + 13
Step 2: 4m − 2m + 4 = 12
Step 3: 2m + 4 = 12

Which of these is most likely the next step?

2m = 3
2m = 8
2m = 16
2m = 18