The correct answer is: B. creep compensation.
Creep compensation is a method used in energy meters to compensate for the effects of creep, which is the slow movement of the meter’s disc due to friction. This is done by adjusting the position of the shading bands, which are metal strips that are placed on the disc. The shading bands block light from the light source, which causes the disc to rotate more slowly.
Friction compensation is a method used in energy meters to compensate for the effects of friction between the meter’s disc and the bearings. This is done by adjusting the position of the friction compensation weights, which are small weights that are placed on the disc. The friction compensation weights help to reduce the amount of friction between the disc and the bearings, which makes the meter more accurate.
Braking torque is the torque that is required to stop the meter’s disc from rotating. This is done by applying a force to the disc, which can be done by using a brake or by using a spring. The braking torque is important because it ensures that the meter does not over-run when it is turned off.
None of the above is not the correct answer because it does not describe any of the methods that are used to compensate for the effects of creep, friction, or braking torque in energy meters.