Which of the following statements is correct?

Correct option is B

The correct answer is (B) The direction of the magnetic field around a straight current-carrying conductor can be given by the Right-Hand Thumb Rule.

Explanation:
• The Right-Hand Thumb Rule (also known as Maxwell's corkscrew rule) states that if you imagine holding a current-carrying straight conductor in your right hand such that the thumb points towards the direction of current, then your fingers will wrap around the conductor in the direction of the field lines of the magnetic field.
• This represents a fundamental relationship between electricity and magnetism, illustrating how moving electric charges generate concentric magnetic circular fields.

Information Booster:
• Oersted's Discovery: Hans Christian Oersted was the first to observe that a compass needle deflects near a current-carrying wire, proving that electricity and magnetism are linked.
• Fleming's Left-Hand Rule: Used to find the direction of force acting on a current-carrying conductor placed in a magnetic field (useful for electric motors).

Additional Knowledge:
• Option A: Incorrect. Outside a magnet, magnetic field lines always emerge from the North pole and merge at the South pole (inside, they go South to North).
• Option C: Incorrect. Magnetic field lines form continuous closed continuous curves; they are not strictly straight unless uniformly applied over an infinitely small area.
• Option D: Incorrect. The magnetic field is actually strongest directly on or very close to the surface of the current-carrying wire and decreases inversely with distance.