Magnetic flux through any closed surface around magnetic pole is always zero. The correct reason for this fact, is

Magnets always exist in pairs Magnets are always dipoles Magnets can exist as monopoles No magnet exerts force on another magnet

Magnets are always dipoles

The correct answer is Option (2) → Magnets are always dipoles Magnets are always dipoles. So net magnetic flux through any closed surface around magnetic pole is zero.