Two particles A and B of equal masses have velocities $$\vec{v_A} = 2\hat{i} + \hat{j}$$ and $$\vec{v_B} = -\hat{i} + 2\hat{j}$$. The particles move with accelerations $$\vec{a_A} = -4\hat{i} - \hat{j}$$ and $$\vec{a_B} = -2\hat{i} + 3\hat{j}$$ respectively. The centre of mass of the two particles moves along

A

a straight line

B

a parabola

C

a circle

D

an ellipse