Hello..!
If you say that the value of x is an integer then the number when divided by 3 which is "3x" will result in an integer:

Option A) does NOT return an integer so it is not the answer.

Option B) is also not the answer.

Option C) does result in an integer but let's see the others:

Option D) also does not return an integer.

And lastly option E) does not result in an integer so the only one that results in an integer is option C) and that is the 42nd answer.

So, the correct part is C)42°