Either aluminum or zinc will replace silver ion in silver nitrate to give silver metal and aluminum nitrate or silver metal and zinc nitrate

1) Redox reaction: Al + 3AgNO₃ → Al (NO₃) ₃ + 3Ag.

oxidation number of aluminium change from 0 to + 3 (oxidation).

oxidation number of silver changes from + 1 to 0 (reduction).

2) Redox reaction: Zn + 2AgNO₃ → Zn (NO₃) ₂ + 2Ag.

oxidation number of zinc change from 0 to + 2 (oxidation).

oxidation number of silver changes from + 1 to 0 (reduction).