Answer:
Figure A - hexagon
Figure B - triangle
Figure C - rectangle
Figure D - octagon
Explanation:
If figure B has 3 vertices (angles), then that means it is a triangle (3 sides)
So that means figure A has 6 sides, (hexagon)
And figure D has 8 vertices, so 8 sides (octagon)
And if C has half as many, that would be 4 (rectangle)