Answer:
B
If you just use you finger to keep track of one point and follow each set of instructions you will find that B is correct.
I realize that in a previous comment I had said im bad at geometry but I immediately assumed this had to do with ASA and such.
Did you not include D or finish writing D since the first three are not right. If one of the possible answers is that they are alternate exterior angles or the same degrees, that would be the answer.
Answer: 30
You find the difference and put this over the original price ie. 25-20=5. 5/20= 0.25 so the increase is 25%
24x 0.25= 6
6+24=£30
(Or 24x1.25=30)