Multiple choice Which of the following is used as an anti-knocking agent? Feron Glycol Glyoxal TEL All of these Reveal answer Fill a bubble to check yourself D Correct answer Explanation Anti-knocking agents are those compounds, which on adding gasoline in a very small quantity reduce knocking. TEL (C2H5)4Pb is added the extent of only 0.01% in gasoline as antiknocking compound.