The correct answer is option 4, "Graphite has a tetrahedral structure." This statement is not correct.

Let`s dissect each option to better understand them:

Option 1: "Graphite is a non-metal." This statement is correct. Graphite is indeed a non-metal. It is a form of carbon with a unique molecular structure.

Option 2: "Graphite is an allotrope of carbon." This statement is correct. Allotropes are different forms of the same element, and graphite is one of the allotropes of carbon.

Option 3: "Graphite is a conductor of electricity." This statement is correct. Graphite is an excellent conductor of electricity due to its unique structure and arrangement of atoms.

Option 4: "Graphite has a tetrahedral structure." This statement is not correct. Graphite has a layered structure, where each layer consists of hexagonal rings of carbon atoms. This layered structure gives graphite its unique properties, such as its lubricating nature and electrical conductivity.

In conclusion, option 4 is incorrect as graphite does not have a tetrahedral structure.