**Core Concept**
Disinfectants are chemical agents designed to inactivate or kill microorganisms on non-living surfaces, often used in healthcare settings to reduce the transmission of infections. They work by denaturing proteins, disrupting cell membranes, or interfering with cellular processes.

**Why the Correct Answer is Right**
The correct answer will be a statement that contradicts the established principles of disinfectant action. Disinfectants typically work by exposing microorganisms to a chemical agent that disrupts their cellular processes, leading to death or inactivation. This can involve the denaturation of proteins, disruption of cell membranes, or interference with essential cellular processes.

**Why Each Wrong Option is Incorrect**
**Option A:** Disinfectants can be effective against a broad spectrum of microorganisms, including bacteria, viruses, and fungi. Incorrect because this statement is generally true for many disinfectants.
**Option B:** Disinfectants often require a certain contact time to be effective against microorganisms. Incorrect because this statement is also true for many disinfectants.
**Option C:** Disinfectants can be classified based on their level of effectiveness against different types of microorganisms. Incorrect because this statement is true and relevant to disinfectant classification.

**Clinical Pearl / High-Yield Fact**
When selecting a disinfectant, it's essential to consider the type of surface being disinfected, the level of microbial contamination, and the desired level of disinfection (e.g., high-level disinfection for medical devices, low-level disinfection for non-critical surfaces). Always follow the manufacturer's instructions and recommended contact times.

**Correct Answer: D.**