**Core Concept**
Oxidoreductases are a class of enzymes that catalyze the transfer of electrons from one molecule to another, resulting in a change in oxidation state. This process is essential in various biochemical pathways, including cellular respiration, photosynthesis, and detoxification.

**Why the Correct Answer is Right**
Oxidoreductases typically contain cofactors such as flavin adenine dinucleotide (FAD), nicotinamide adenine dinucleotide (NAD+), or iron-sulfur clusters that facilitate the transfer of electrons. Examples of oxidoreductases include cytochrome P450, xanthine oxidase, and lactate dehydrogenase. These enzymes play crucial roles in various metabolic pathways, and their dysfunction can lead to various diseases.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is not a class of enzymes that catalyze oxidation-reduction reactions. *However, it is a type of enzyme that catalyzes the hydrolysis of molecules.*

**Option B:** This option is incorrect because it is not a class of enzymes that catalyze oxidation-reduction reactions. *However, it is a type of enzyme that catalyzes the transfer of phosphate groups.*

**Option C:** This option is incorrect because it is not a class of enzymes that catalyze oxidation-reduction reactions. *However, it is a type of enzyme that catalyzes the hydrolysis of peptide bonds.*

**Clinical Pearl / High-Yield Fact**
Oxidoreductases play a crucial role in the metabolism of various drugs, including the cytochrome P450 enzymes that metabolize many medications. Understanding the role of oxidoreductases is essential in pharmacology and toxicology.

**Correct Answer: D.**