MCQ
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 $- 1$ : Sky wave signals are used for long distance radio communication. These signals are in general, less stable than ground wave signals.
Statement $- 2$ : The state of ionosphere varies from hour to hour, day to day and season to season.
  • A
    Statement$-1$ is true, Statement$-2$ is true, Statement$-2$ is the correct explanation of Statement$-1.$
  • Statement$-1$ is true, Statement$-2$ is true, Statement$-2$ is not the correct explanation of Statement$-1.$
  • C
    Statement$- 1$ is false, Statement$- 2$ is true.
  • D
    Statement$- 1$ is true, Statement$- 2$ is false

Answer

Correct option: B.
Statement$-1$ is true, Statement$-2$ is true, Statement$-2$ is not the correct explanation of Statement$-1.$
b
For long distance communication , sky wave signals are used.

Also, the state of ionosphere varies every time. so, both statement are correct.

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