We have two parallel lines and one that passes through them diagonally.
Also, the <1 is 135°, and they ask for <2.
As we know, the parallel lines imply that the addition of its angles must be 180°
Then <2+<3=<180°
And again for the parallel lines, we have that the angle <1 must be equal to angle <3.
Then:

Then the correct answer is <2=45°