This question has Statement $-1$ and Statement $-2.$ Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement $-1:$ Short wave transmission is achieved due to the total internal reflection of the $e-m$ wave from an appropriate height in the ionosphere.
Statement $-2:$ Refractive index of the ionosphere is independent of the frequency of $e-m$ waves.
Statement $-1:$ Short wave transmission is achieved due to the total internal reflection of the $e-m$ wave from an appropriate height in the ionosphere.
Statement $-2:$ Refractive index of the ionosphere is independent of the frequency of $e-m$ waves.
- AStatement $-1$ is true,Statement $-2$ is false.
- BStatement $-1$ is false,Statement $-2$ is true.
- CStatement $-1$ is true,Statement $-2$ is true but Statement $-2$ is not the correct explanation of Statement $-1$.
- DStatement $-1$ is true,Statement $-2$ is true and Statement $-2$ is the correct explanation of Statement $-1$.
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