Current is directly proportional to voltage and inversely proportional to what?

The relationship described in the question is grounded in Ohm's Law, which states that current (I) is directly proportional to voltage (V) and inversely proportional to resistance (R). This can be mathematically expressed as ( I = \frac{V}{R} ).

In this equation, if the voltage increases while the resistance remains constant, the current will also increase, demonstrating the direct proportionality. Conversely, if the resistance increases while the voltage is constant, the current decreases, highlighting the inverse relationship between current and resistance.

The other concepts listed, such as capacitance, power, and impedance, while related to electrical systems, do not establish the same direct and inverse relationship as seen with voltage and resistance in this context. Therefore, resistance is the correct answer, as it is the parameter that directly influences the current in the way described.