The correct answer is option 1: each carbon atom in graphite undergoes sp2 hybridization and forms three sigma bonds with three neighboring carbon atoms.

In graphite, each carbon atom is bonded to three other carbon atoms through strong covalent bonds. These bonds are formed through sp2 hybridization, where the carbon atom combines one s orbital and two p orbitals to form three sigma bonds. This hybridization allows the carbon atoms to arrange themselves in a hexagonal lattice structure, similar to a honeycomb.

The presence of these strong covalent bonds between carbon atoms allows for efficient conduction of both heat and electricity. The delocalized electrons in the graphite structure can move freely along the layers, enabling electricity to flow easily. Likewise, the bonds between carbon atoms allow for rapid transfer of thermal energy, making graphite an excellent conductor of heat.

Option 2, sp5 hybridization, is not accurate because carbon typically undergoes sp3 hybridization when forming tetrahedral structures, such as in diamond.

Option 3, tetrahedrally bonded, is incorrect because tetrahedral bonding refers to the arrangement of atoms around a central atom, which is not the case in graphite.

Option 4, being free from Van der Waals force, is unrelated