The correct option is C detect the presence of charge and test the kind of charge
Answer is D.
The gold leaf electroscope has been used by physicists for hundreds of years. It indicates the presence and nature of a charge through the application of charge to a metal top plate connected through a stem to two pieces of gold leaf. The movement of one piece of gold leaf away from the other shows that the electroscope is charged.
Hence, a gold leaf electroscope can detect the presence of charge and test the kind of charge.