(07.03 lc)

the steps below show the incomplete solution to find the value of p for the equation 4p − 2p + 4 = −1 + 21:

step 1: 4p − 2p + 4 = −1 + 21
step 2: 4p − 2p + 4 = 20
step 3: 2p + 4 = 20

which of these is most likely the next step?
2p = 5
2p = 8
2p = 16
2p = 24