The correct answer is option 3, which states that points A and C indicate an unstable state of an object. To understand why this is the correct answer, let`s analyze each option:

Option 1: Only Point A - This option suggests that only Point A indicates an unstable state. However, looking at the figure, we can see that Point A is on the initial stable position, so this option is incorrect.

Option 2: Only Point B - This option suggests that only Point B indicates an unstable state. However, Point B is on a position of stable equilibrium, so this option is incorrect.

Option 3: Points A and C - This option states that both Point A and Point C indicate an unstable state. Looking at the figure, we can see that Point A is the initial stable position, and Point C is a position in which the object is displaced but not in stable equilibrium. Therefore, this option is correct.

Option 4: Points B and D - This option suggests that both Point B and Point D indicate an unstable state. However, Point B is a position of stable equilibrium, and Point D is a position of neutral equilibrium where the object will remain without oscillating. Therefore, this option is incorrect.

In conclusion, while options 1,