If I just write it down as the text goes:
1 + 3x < 3 + x
So this is an inequality that represents the statement.
Now, option A is not the same (incorrect)
option B is not even an equality (maybe a typo?)
option C is missing
option D seems like a match EXCEPT is it not an inequality - it should have the "<" sign as in my answer above.
Could it be that the missing option C matches. Let me know in the comments section.