Which group or groups of atoms are the only atoms with f orbitals A. All atoms heavier than barium B. All atoms heavier than krypton C. All noble gases D. Lanthanides and actinides

All atoms heavier than barium

Explanation:

In the periodic table, elements are divided into blocks. We have the;

s - block elements

p - block elements

d - block elements

f - block elements

However, immediately after Barium, we now encounter elements that have f-orbitals. Barium possesses a fully filled d-orbital. Hence after it, we see elements with 4f and 5f orbitals called the Lanthanides and actinides. The elements following the lanthanide and actinide series possess completely filled f-orbitals as inner orbitals.

Hence elements heavier than barium all possess f-orbitals.