Answer:
He did not add 13 to 26.
Explanation:
Given : Step 1: x − 13 = 26
Step 2: x = 26 − 13
Step 3: x = 39
To Find: Which statement best explains why Step 2 is incorrect in Colton’s solution?
Solution:
Correct steps
Step 1:

Step 2:

Step 3:

So, this concludes that He did not add 13 to 26 in step 2
So, Option C is correct.
Hence He did not add 13 to 26.