**Core Concept**
Peroxidase enzyme is a peroxidase-catalase enzyme family member involved in the breakdown of hydrogen peroxide. It plays a crucial role in various cellular processes, including the detoxification of reactive oxygen species.

**Why the Correct Answer is Right**
Peroxidase is used in estimating the concentration of hydrogen peroxide (H2O2) in a solution. This is achieved through a colorimetric reaction where the peroxidase enzyme catalyzes the oxidation of a chromogen, resulting in a colored product that can be measured spectrophotometrically. The intensity of the color is directly proportional to the concentration of hydrogen peroxide in the solution.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because peroxidase is not typically used for estimating glucose concentrations.
**Option B:** This option is incorrect because the enzyme glucose oxidase is used for estimating glucose concentrations, not peroxidase.
**Option C:** This option is incorrect because peroxidase is not typically used for estimating lactate concentrations.

**Clinical Pearl / High-Yield Fact**
A common clinical application of peroxidase enzyme is in the estimation of hydrogen peroxide in wound care, where it is used to evaluate the effectiveness of disinfection.

**Correct Answer: D.**