Final answer:
Indium (In) has larger atoms compared to Aluminum (Al).
Step-by-step explanation:
The element with larger atoms in the given pair, Al or In, is In (Indium).
The atomic radius generally decreases from left to right across a period and increases from top to bottom in a group in the periodic table.
Indium is located below Aluminum in the periodic table, so it has larger atoms compared to Aluminum.