Which of the following is the main enzyme responsible for activation of xenobiotics?

Xenobiotics are compounds which may be accidently ingested or taken as drugs or compounds produced in the body by bacterial metabolism. The cytochrome P-450 enzyme family is involved in the biotransformation reaction of xenobiotics. They are heme containing membrane proteins localized in the smooth endoplasmic reticulum of liver. They are so named because they absorb light at wavelength of 450nm, when exposed to carbon monoxide. Ref: Vasudevan Biochemistry, 3rd Edition, Pages 310-2