The correct answer is: C. both (A) and (B).
The diversity factor is a measure of the variability of the load on a power system. A higher diversity factor indicates that the load is more variable, and a lower diversity factor indicates that the load is more constant.
The fixed cost of unit generated is the cost of generating electricity that is independent of the amount of electricity generated. This includes costs such as the cost of building and maintaining power plants.
The running cost of unit generated is the cost of generating electricity that is dependent on the amount of electricity generated. This includes costs such as the cost of fuel and the cost of operating power plants.
The diversity factor has a direct effect on both the fixed cost of unit generated and the running cost of unit generated. A higher diversity factor means that the load is more variable, and this means that the fixed cost of unit generated will be higher. This is because the power plant must be able to meet the peak load, even if the average load is lower.
A higher diversity factor also means that the running cost of unit generated will be higher. This is because the power plant must be able to respond quickly to changes in the load, and this requires more expensive equipment.
In conclusion, the diversity factor has a direct effect on both the fixed cost of unit generated and the running cost of unit generated. A higher diversity factor means that the load is more variable, and this means that both the fixed cost of unit generated and the running cost of unit generated will be higher.