The correct option is
D Parallelogram

Consider a quadrilateral ABCD such that mid-points on its sides AB, BC, CD and DA are P, Q, R and S respectively.
In
ΔADC, S and R are the mid-points of sides AD and CD respectively.
In a triangle, the line segment joining the mid-points of any two sides of the triangle is parallel to the third side and is half of it.
∴SR||AC and
SR=12AC.....(i)
In
ΔABC, P and Q are mid-points of sides AB and BC respectively. Therefore, by using mid-point theorem,
PQ||AC and
PQ=12AC .....(ii)
Using (i) and (ii), we obtain
PQ||SR and
PQ=SR …..(iii)
Clearly, one pair of opposite sides of quadrilateral PQRS is parallel and equal.
Hence, PQRS is a parallelogram.
Hence, the correct answer is option (d).