Match layer of ionosphere with the height of the layer from surface of the Earth.

a) D	e) 250 - 400 km
b) E	f) 100 km
c) F	g) 65 - 75 km
d) F${}_2$	h) 170 - 190 km

The correct option is B a-g, b-f, c-h, d-e
The layers of ionosphere are spaced above the Earth's surface as given below:
The D layer is the innermost layer, $60km$ ($37miles$) to $90km$ ($56miles$) above the surface of the Earth.
The E layer is the middle layer, $90km$ ($56miles$) to $120km$ ($75miles$) above the surface of the Earth.
The F layer or region, extends from about $200km$ ($120miles$) to more than $500km$ ($310miles$) above the surface of Earth.
The $F_2$ layer exists from about $220$ to $800km$ above the surface of the Earth..