According to VSEPR (Valence Shell Electron Pair Repulsion) theory, the molecular shape of AsF3 should be classified as trigonal pyramidal, because the arsenic atom forms three single covalent bonds with fluorine atoms and has one lone pair of electrons. This lone pair affects the geometry of the molecule, resulting in a trigonal pyramidal shape rather than a tetrahedral one.
So the correct response is:
trigonal pyramidal, because the arsenic atom forms three single covalent bonds and has one lone pair.