The value of ∇.A; where \[A = 3xy{\overrightarrow a _x} + x{\overrightarrow a _y} + xyz{\overrightarrow a _z}\]     at a point (2, -2, 2) is:

A. Radar B. Direction finding C. Satellite communication D. All of the above

A. Scalar B. Vector C. Unit vector D. None of the above

A. Hertz antenna B. Marconi antenna C. Folded dipole D. None of the above

A. Accelerating B. Retardation C. Oscillating D. Lagging the current