Which of the Following Statements About Free Radicals Is Incorrect

Which of the following statements about free radicals is incorrect?

A) They are a by-product of oxygen-consuming redox reactions.
B) Their unpaired electron makes them extremely reactive.
C) They can disrupt covalent bonds in biomolecules.
D) B vitamins provide protection from their harmful effects.
E) Superoxide catalase is one of the specific enzymes that can provide protection from their harmful effects.