The correct answer is B. Infinite.
An ohmmeter is a device used to measure electrical resistance. When an ohmmeter is connected to an open resistor, there is no current flow through the resistor, and the ohmmeter will read infinity. This is because there is no path for the current to flow through.
Option A is incorrect because a zero reading would indicate that there is no resistance, which is not possible for an open resistor. Option C is incorrect because a high reading would indicate that there is some resistance, which is also not possible for an open resistor. Option D is incorrect because a low reading would indicate that there is some resistance, but not enough to be considered an open circuit.