The figure formed by joining the mid-points of the adjacent sides of a rhombus is a square        (b)  rectangle    (c)  trapezium    (d)  none of these

Explanation

By mid-point theorem

In `triangleABD`, `EH |\ | BD` (Mid-point theorem)

In `triangleCBD`, `FG |\ | BD` (Mid-point theorem)

In `triangleACD`, `GH |\ | AC` (Mid-point theorem)

In `triangleABC`, ` EF |\ | AC` (Mid-point theorem)

As, `ACbotBD`

`therefore` adjacent sides of quadrilateral EFGH are perpendicular Rectangle .

Hence, option (b) is correct.