Magnetic induction in soft iron creates opposite poles adjacent to a magnet's pole

Steps:

• The south pole of M2 induces a north pole in the near side of X, with south on X's far side, as shown.
• X's south pole then induces a north pole in the near side of M3, polarizing M3 accordingly.
• M3's south pole (far side from X) induces a north pole in Y's near side.
• Y's far side becomes south, but diagram labeling shows NW configuration matching this induction pattern.

Why B is correct:

• Lenz's law dictates that induced poles oppose the inducing field; M3's south pole induces north in Y's near side, leading to NW labeling as per the diagram's orientation.

Why the others are wrong:

• A (NS): Would require M3's north pole inducing south in Y, contradicting the chain from X.
• C (SN): Reverses the induction direction, ignoring the opposing pole rule.
• D (SS): Impossible, as iron cannot have identical poles on both ends without external field reversal.

Final answer: B