Correct Answer - A::B::D
Description of motion is completely specified if we know the variation of x as a function of time. For simple harmonic motion, the general equation of motion is `x=A(omegat+delta)`. As `omega` is given to describe the motion completely, we need the values of A and `delta`. From options (b) and (d) we can have the value of A and `delta` derectly. For option (a) we can find A and `delta` if we know initial velocity and initial position. Option (c ) cannot give the value of A and `delta` so it is not the correct condition.