Why is potassium fluoride added to the electrolyte in the extraction of sodium from fused sodium chloride?

A.

Pure sodium chloride does not conduct electricity

B.

Potassium fluoride prevents the sodium produced from attacking the electrodes

C.

Potassium fluride increases conductivity

D.

Potassium fluride reduces the temperature at which sodium chloride fuses

E.

the potassium fluride acts as a catalyst

Correct answer is D

No explanation has been provided for this answer.