Assertion : The sum of squares of cosines of angles made by a vector with X, Y and Z axes is equal to unity.
Reason : A vector making `45^(@)` with X-axis must have equal components along X and Y-axes.
A. If both Assertion & Reason are Tune & the Reason is a correct explanation of the Assertion. `
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.
