Answer:
D. Place the point of the compass on the midpoint of AB and mark
the points directly above and below the midpoint.
Explanation:
Below are the simple steps to follow to draw a perpendicular bisector of line AB.
First step
Set the compass at the end of one line segment and move the compass so that it would be slightly longer than half of the line AB.
Second step
Set the compass at point A and make some arcs just above line AB.
Third step
Draw an arc from point B with the same compass width.
Fourth step
Carefully set a ruler at the intersection of the arcs and draw the line segment.