Final answer:
The site of steroid synthesis, drug detoxification, and lipid metabolism is the Endoplasmic Reticulum, involved specifically in these processes through its smooth variant.
Step-by-step explanation:
The site of steroid synthesis, drug detoxification, and lipid metabolism is B) Endoplasmic Reticulum.
Both peroxisomes and the endoplasmic reticulum play crucial roles in various cellular processes. Peroxisomes are known primarily for detoxifying harmful substances and oxidizing fatty acids, often producing hydrogen peroxide (H₂O₂) as a byproduct, which they can convert into water and oxygen. However, it is the smooth endoplasmic reticulum (ER) that is involved specifically in lipid metabolism, steroid biosynthesis, and the detoxification of drugs and toxic compounds. The rough ER, with its ribosomes, is more associated with protein synthesis.