The voltage in a circuit is related to the amount of what in the circuit? Energy
Power
Time
Charge

Charge

I hope this helps

Energy

Explanation:

when we speak of an amount of voltage being present in a circuit, we refer to the measurement of how much potential energy exists to move charge carriers from one particular point in a circuit to another point in the same circuit

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.