It’s B, because VKQ is equal to DKJ. VKQ is 153°, which makes DKJ 153°. But you’re trying to find DKM, which is 153°(the total degree) minus MKJ, the other half not including the one you’re trying to find. But we see a square there, a right angle, meaning that MKJ is equal to 90°
So we take the total of DKM (153°) and subtract it by the half that we know (which is MKJ, 90°) in order to find the half that we don’t know (DKM)
So it’s simply 153-90, which is 63°, so the answer should be B.
Hope this helped if you have other questions regarding this let me know! I know it seems a little confusing