it’s B, (the second answer from the top). the numbers next to the letters are actually coordinates (like on a coordinate system). 1st tile: |SR|=|PQ|=2, |SP|=|RQ|=6, so |SR|:|SP|=2:6=1:3; 2nd tile: |ML|=|JK|=1, |MJ|=|LK|=3, so |ML|:|MJ|=1:3. The tiles have the same ratios therefore they are similar :)
