Which of the following metal cannot occur in native state?

Al

K,Na,Ca,Mg,Al → High Reactivity
Zn,Fe,Pb,Cu→ Moderate Reactivity
Ag,Au→ Low reactivity
⇒ Aluminium cannot occur in the native state. It occurs naturally in the form of oxides.
⇒ It is at the top of the electrochemical series which shows it has a high reacting nature.
⇒ So, it occurs naturally with other elements in combination.