Final answer:
Zinc (Zn) is not considered a transition element because it does not form ions with incompletely filled d orbitals as its common +2 ion has a fully filled d subshell. The correct answer is option: (d) zinc.
Step-by-step explanation:
The question asks which of the following is not considered a transition element: scandium (Sc), silver (Ag), vanadium (V), or zinc (Zn). A transition element is defined as an element that has one or more stable ions with incompletely filled d orbitals. Based on this definition, the element that is not considered a transition metal among the options given is zinc (Zn).
Zinc, with the atomic number 30, has a fully filled d subshell in its most commonly occurring oxidation state, which is Zn+2, where the electronic configuration is [Ar]3d10. This means that it does not have incompletely filled d orbitals as a stable ion and thus, does not fit the criteria for being a transition metal. In contrast, scandium, silver, and vanadium are considered transition metals because they can form ions with partially filled d orbitals.