Hope I'm looking at the same question.
Elements, speaker orientation, shading of speaker, position of ball, colour of ball.Starting at the end of the sequence and working from right to left (gives three in a sequence so more info.) using a bit of hindsight/foresight?
Shading slant/horizontal/slant/?/slant so ?=horizontal (slants are all same top left to bottom right)
eliminate a and b
Speaker orientation c d e all same.
Ball Colour white/black/white/?/white so black
leaves c and e
Ball position right/left/right/?/top???
so ignoring the last odd top ball position? I would say ball = left
so answer is C
Looks like the first shape in the sequence has a mistake in the ball position!
We have not ticked off the level 4 & 5 questions as being completed satisfactorily, I think these higher level questions have been a bit rushed in this book, which is otherwise brilliant.