Final answer:
Elements that have electrons in both the highest occupied s sub-level and an f sub-level are known as f-block elements, which include the lanthanides and actinides. These metals have a typical electron configuration that includes (n-2)f electrons along with the highest s electrons.
Step-by-step explanation:
The question asks which type of element has electrons in both the highest occupied s sub-level and an f sub-level. Analyzing the provided information, we come to understand that main group elements have their last electron entering an s or p orbital, while transition elements have the last electron entering a d orbital. Neither of these match the criteria directly. However, for the f-block elements, the electron configuration includes (n-2)f electrons, in addition to the s electrons of the highest principal energy level. These elements belong to the lanthanides and actinides, which fill the 4f and 5f sublevels respectively, and are positioned in the periodic table separate from the main group and transition elements.
The f-block elements are typically metals and have both the highest occupied s sub-level and a partially filled f sub-level. Therefore, the category of elements that has its highest occupied s sub-level and a f sub-level contain electrons would be the f-block elements, which include the lanthanides and actinides.