State Ohm's law.

• A. R = I / V
• B. V = I × R
• C. P = V × I
• D. V = I + R

Answer: (B)

Ohm's law describes how voltage, current, and resistance relate to each other. It says that the voltage across a conductor equals the current through it times its resistance. In symbols: V = I × R. This tells you that if you know the current and the resistance, you can find the voltage, and if you know voltage and resistance, you can find the current (I = V / R). The units also line up correctly: amperes times ohms give volts.

Other forms shown aren’t correct representations of the basic relationship. For example, R = I / V is inverted — the correct form for resistance is V / I. The expression P = V × I is a valid, related formula (power), derived from Ohm's law, but it’s not the direct voltage–current–resistance relationship. And V = I + R mixes quantities that don’t add together in this context, so it’s not valid.