A concentric spring consist of two helical compression springs
(A) both springs always have right hand helix
(B) both springs always have left hand helix
(C) both springs always have opposite hand of helices
(D) any of the above
(A) both springs always have right hand helix
(B) both springs always have left hand helix
(C) both springs always have opposite hand of helices
(D) any of the above