When 38 is divided by 4, the remainder is 2. So, 4 is not a factor of 38.
When 52 is divided by 6, the remainder is 4. So, 6 is not a factor of 52.
When 33 is divided by 5, the remainder is 3. So, 5 is not a factor of 33.
When 96 is divided by 8 the remainder is 0. So, 8 is a factor of 96.