Answer: The correct option is B. The point U is the centroid of RST.
Exclamation:
From the given figure it is noticed that the line SU divides the angle S in two equal parts, so the line SU is a part of median line and when the line SU extended until the sideRT is being touched, we get a median line.
The line TU divides the angle T in two equal parts, so the line TU is a part of median line and when the line TU extended until the sideRS is being touched, we get a median line.
The line RU divides the angle R in two equal parts, so the line RU is a part of median line and when the line RU extended until the sideTS is being touched, we get a median line.
The point where the all median of a triangle intersects each other is called centroid.
From the figure we can conclude that all the median of the triangle RST are intersecting on point U, therefore point U is the centroid and option B is correct.
