Correct option is A
The cores of large power transformers are made from cold-rolled grain oriented (CRGO) steel. CRGO steel is a soft magnetic material with many desirable properties, including:
· High permeability: CRGO steel has high magnetic permeability.
· Low hysteresis loss: CRGO steel has low hysteresis loss.
· High resistance: CRGO steel has high resistance.
· Reduced magnetostriction: CRGO steel has reduced magnetostriction.
· High stacking or laminating factor: CRGO steel has a high stacking or laminating factor.
· Low losses: CRGO steel has low losses.
· Increased corrosion resistance: CRGO steel increases corrosion resistance.
