Answer:
Silver
Step-by-step explanation:
Silver (Ag) will not react with sulfuric acid (H2SO4(aq)) by single displacement reaction. This is because in the electrochemical series (activity series), silver is below hydrogen and it's less reactive.
The other elements stated (Zinc, Magnesium, Iron) are higher than hydrogen in the activity series and will definitely displace hydrogen in single displacement reaction.
A single-displacement reaction is known as a chemical reaction which occurs which one element is actually replaced or displaced by another in a compound. We represent it as:
B + D-C ➡️ B-C + D
This will readily take place if B is more reactive than D, and it will finally give a more stable product.