Assertion : Parallax method cannot be used for measuring distance of stars morer then 100 light year away.
Reason : Because parallax angle reduces so much that it cannot be measured accurately.

Options

A. if both assertion and reason are true reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation fo assertion.
C. If assertion is true but reaso is false.
D. IF both assertion and reason are false.

Answer

A

Explanation

As the distance of star increases, the parallax angle decreases, and great degree of accuracy is required for its measurement. Keeping in view the practical limitation in measuring the parallax angle, the maximum distance of a star we can measure by parallax method is limited to 100 light year.