O or Oxygen because it needs electrons to be stable causing it to be an anion with a 2- charge to have a complete shell while Aluminum would be an cation with a 3+ charge, Potassium or K with a 1+ charge, and Argon wouldn’t be an anion because it is a noble gas and is already stable and don’t need electrons due to a full shell.
Organism: Apple All cells from the apple come from cell division occurring from the apple in order for it to grow. An apple has multiple cells The small living part in an apple is a cell thus showing that cells are the basic living unit.