Which of the following statement are correct ?
A. Magnetisation of a sample is equal to its magnetic moment per unit volume.
B. For measuring currents, the galvanometer has to be connected in parallel in the circuit.
C. In an ideal toroid the coils are circular.
D. In larger the number of field lines crossing per unit area, the stronger is the magnitude of magnetic field.
E. The currents flowing in the same direction attract each other.
Choose the correct answer from the options given below :

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.