P-Type Semiconductor:
A P-type semiconductor is a type of semiconductor material that has been doped with impurities to create an excess of positive charge carriers or "holes" in the crystal lattice. This results in a material with a predominance of positive charge carriers and a relatively low concentration of negative charge carriers or electrons. P-type semiconductors are commonly used in electronic devices such as diodes, transistors, and solar cells.

Doping:
Doping is the process of intentionally adding impurities to a pure semiconductor material in order to alter its electrical properties. The impurities used for doping are typically elements from Group V or Group III of the periodic table.

Gallium Doping:
In the case of P-type semiconductors, impurities from Group III are used for doping. Among the options given, gallium (Ga) belongs to Group III and can be used to dope pure silicon (Si) to create a P-type semiconductor.

Gallium Doping Process:
1. Pure silicon is obtained, which consists of a crystal lattice of silicon atoms.
2. Gallium atoms are introduced into the crystal lattice by a process called doping.
3. Gallium has three valence electrons, while silicon has four valence electrons. When a gallium atom replaces a silicon atom in the crystal lattice, there is a deficiency of one electron, resulting in a positively charged "hole" in the lattice.
4. These positively charged holes act as charge carriers in the P-type semiconductor.
5. The excess of positive charge carriers makes the material P-type, as it has a predominance of positive charge carriers (holes) and a relatively low concentration of negative charge carriers (electrons).

Conclusion:
Adding gallium to pure silicon can result in a P-type semiconductor by introducing positively charged holes into the crystal lattice. This doping process alters the electrical properties of the material, making it suitable for various electronic applications.