$V_2O_5$ catalyst is used in the manufacturing of

Sulphuric acid

The correct answer is Option (3) → Sulphuric acid

Vanadium(V) oxide (V₂O₅) is used as a catalyst in the contact process for the industrial manufacture of sulphuric acid (H₂SO₄). It helps in the oxidation of SO₂ to SO₃:

$2 SO_2 + O_2 \overset{V_2O_5}{\longrightarrow} 2 SO_3$

This is a key step in the contact process before SO₃ is absorbed in water to form H₂SO₄.