Q: In which of the following cases, the centre of mass of a metallic rod is definitely not at its centre? I. The density of the metallic rod continuously decreases from left to right. II. The density of the metallic rod continually increases from left to right. III. The density of the metallic rod decreases from left to right up to the centre and then increases. IV. The density of the metallic rod increases from left to right up to the centre and then decreases. Select the correct answer using the code given below.