The correct answer is C. Silver plated mica capacitor.
Paper capacitors are made of two sheets of paper separated by a thin layer of aluminum foil. The paper is impregnated with an insulating material, such as wax or oil. Paper capacitors are relatively inexpensive and have a good range of capacitance values. However, they are not very stable and can have a significant variation in capacitance.
Ceramic capacitors are made of ceramic material, such as aluminum oxide or titanium dioxide. They are very small and have a high capacitance value for their size. However, they are also very sensitive to temperature and can have a significant variation in capacitance.
Silver plated mica capacitors are made of mica, which is a very stable material. They are also very small and have a high capacitance value for their size. They are also very stable and have very little variation in capacitance.
Therefore, the silver plated mica capacitor is the best choice for a capacitor with the least variation.