You can see that the two large blocks are adjacent which rules out B. The thinner blocks sits inside the larger block which rules out A and C so the answer must be B.
When looking from above, height doesn't matter so the simplest thing to do is work out the outline of the shape. Once you have this you can see that it must be A which is a triangle with a kind of jagged edge.
The blue circle is opposite blue stars so it must be B or D. The big square is clockwise of the blue circle so the answer must be D
The easiest approach is to start as close to the mirror line as possible and work further away. You can see in this case that there are two circles slightly on top of each other so the answer must be A or D. If you assess the positioning of the outer circles, you can see the answer must be A.
Pick a section and rotate it step-by-step. It's easiest if you pick a large section like the orange circles in the top right-hand corner with the blue circle next to it. If you rotate this you can see the answer is C where the same pattern is in the bottom right hand corner.
