Statement-1 : Electromagnetic waves with frequencies smaller than the critical frequency of ionosphere cannot be used for communications using sky wave propagation.
Statement-2: The refractive index of the ionosphere becomes very high for frequencies higher than the critical frequency.

Options

A. Statetment-I is True, Statement-II is True , Statement-II is a correct explanation for Statement-I
B. Statement-I is True, Statement-II is True , Statement-II is NOT a correct explanation for Statement-I
C. Statement-I is True, Statement-II is False
D. Statement-I is False, Statement-II is True

Answer

D