Static Equilibrium Is

Static equilibrium is:

A) When the sum of all external forces acting on an object or body is 1 (∑F = 1) .
B) When an object or body is moving with a constant velocity (i.e. not accelerating) .
C) When an object or body is at rest (i.e. not moving) .
D) When the sum of all external forces acting on an object or body is 1 (∑F = -1) .
E) When an object or body is accelerating at a constant rate.