Which of the following statement is incorrect

Options

A. a,b,c and d must each be a null vector.
B. The magnitude of (a+c) equals the magnitude of (b+d)
C. The magnitude of a can never be greater than the sum of the magnitudes of b,c and d.
D. b+c must lie in the plane of a and d if a and d are not collinear, and in the line of a and d, if they are collinear

Answer

A