We have that the sum of all the angles has to be 360 degrees since klmn is a quadrilateral. The first thing we have to check thus is to cross out the answers that give us a wrong sum. 1 and 3 are the answers that pass this test. Now, we have to decide whether 1 or 3 is correct, which angle is bigger than 90 degrees. Looking at the diagram, we have that M must be larger than N, hence choice 3 is correct. To be clear, the two angles could have different values (60, 114) but they still had to sum to 360 together with K and L