What step is needed when constructing a circle inscribed in a triangle?

This question includes the following list of choices to select the right one: a. construct the angle bisectors of each angle in the triangle. b. construct the perpendicular bisectors of each side of the triangle. c. construct the midpoints of each side of the triangle. d. construct the altitude of each angle in the triangle. the answer is the option b. construct perpendicular bisector of each side of the triangle.that is because the three bisector intercept at one point which is the center of the circle, and the radius is the distance from the center of the circle to the three sides of the triangle.

The answer would be option 4