Below are given some sentences out of which the sentence numbered 1 has been correctly placed. The rest of the sentences A, B, C, D, E, F need to be arranged correctly in order to form a logical order. ​

1. Superconductivity is the occurrence of absolute zero electrical resistance and the expulsion of magnetic fields in certain materials (called superconductors) when these materials are cooled down to a certain temperature.  

A. This means that if we have a loop of superconducting wire, electric current can flow through this wire indefinitely with no power source.

B. In most conductors, this decrease is limited by impurities and other defects.

C. Superconducting transmission lines are more efficient and require less space than traditional power lines resulting in lower energy loss and better environmental impacts.

D. Even at near absolute zero, a normal conductor will show some resistance.

E. However, in a superconductor, the cooling of the material below a certain temperature will make the electrical resistance fall to absolute zero.

F. The lowering of temperature decreases the electrical resistance of conductors.