Given ` vec A + vec B+ vec C + vec D =0`, which of the following statements are correct ?
(a) ` vec A, vec B ,vec C ` abd ` vec D` each must be a null vector.
(b) The magnitude of ` ( vec A + vec C)` equals the magnitude of ` ( vec B + vec D)`.
(c ) The magnitude of ` vec A` can never be greater than the sum of the magnitude of ` vec B , vec C ` and `vec D`.
( d) ` vec B + vec C` must lie in the plane of ` vec A + vec D`. if `vec A` and `vec D` are not collinear and in the line of ` vec A` and `vec D`, if they are collinear.

Options

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