A potentiometer is used to measure the voltage between two points of a DC circuit, which is found to be 1.2V. This is also measured by a voltmeter, which is found to be 0.9V. The resistance of the volt meter is 60 kΩ. The input resistance between two points

A

80 Ω

B

60 Ω

C

20 Ω

D

45 Ω