The resistivity of water should not be less than 1000 Q m. This is because water is a good conductor
of electricity, and if its resistivity is too low, it will allow electricity to flow through it too easily. This could cause problems in electrical appliances and equipment.Option A is incorrect because 10 Q m is too low a resistivity. This would mean that water is a very good conductor of electricity, and it would allow electricity to flow through it too easily. This could cause problems in electrical appliances and equipment.
Option B is incorrect because 100 Q m is still too low a resistivity. This would mean that water is a good conductor of electricity, and it would allow electricity to flow through it too easily. This could cause problems in electrical appliances and equipment.
Option C is incorrect because 1000 Q m is the minimum resistivity that water should have. This means that water is a good conductor of electricity, but it will not allow electricity to flow through it too easily. This will not cause problems in electrical appliances and equipment.
Option D is incorrect because 2000 Q m is too high a resistivity. This would mean that water is a poor conductor of electricity, and it would not allow electricity to flow through it easily. This could cause problems in electrical appliances and equipment.