21. arigid body consisting of three particles a, b,cis constrained such that a, b are rigidly fixed to be at rest. which of the following statements correctly d

21. Arigid body consisting of three particles A, B,Cis constrained such that A, B are rigidly fixed to be at rest. Which of the following statements correctly describes the behaviour of C? (A) C can move on the surface of a sphere of constant radius (B) C can move on the circumference of a circle of constant radius with line joining A, B passing normally through the centre of the circle (C) C can move along the line joining A, B (D) C can move parallel to the line Joining A, B