The correct option is B False
Given: ABCD is a rectangle, M, N,S,T is the mid-point of AB,AD,DC,CB respectively.
Join NS, ST, TM, MN and the diagonals AC and BD.
In a triangle,the line connecting the mid-points of 2 sides parallel to & equals in length the half of the base
NS||MT||AC and MN||ST||BD
NS=MT=12AC; MN=ST=12BD
MNST is a parallelogram ...(The opposite sides of a quadrilateral are parallel & equal)
Now, since AC=BD ....(the diagonals of a rectangle equal)
Thus, MN=NS=ST=TM ...(the half of the equal quantities equal)
Hence, MNST is a rhombus ...(All the sides are equal)