A Type-I superconductor is
1. A conductor of infinite conductivity at all temperature.
2. A conductor with very large conductivity below a critical temperature.
3. A material showing susceptibility = -1 drastically reduced by a critical temperature.
4. A perfect conductor having conductivity drastically reduced by a critical current.
Which of these statements are correct?

A. 1, 2 and 3 only

B. 2, 3 and 4 only

C. 1, 2 and 4 only

D. 1, 2, 3 and 4

Answer: Option B