(a) an anti-particle of the electron

(b) a vacancy created when an electron leaves a covalent bond

(c) absence of free electrons

(d) an artificially created particle

Answer:

The correct option is (b) a vacancy created when an electron leaves a covalent bond

Explanation:

Covalent bonds between atoms of the same or different types bind semiconductor atoms. When an electron leaves its location and becomes free due to thermal agitation, it leaves a void in the bond (covalent), which is known as a hole.