**Core Concept**
Chronic granulomatous disorder (CGD) is a primary immunodeficiency characterized by recurrent life-threatening infections, particularly with catalase-positive bacteria and fungi. It results from a defect in the phagocytic cells' ability to kill ingested microorganisms due to impaired production of reactive oxygen species (ROS).

**Why the Correct Answer is Right**
The correct answer is related to the NADPH oxidase complex, specifically the gp91phox component, which is crucial for the production of ROS in neutrophils and macrophages. In CGD, mutations in the CYBB gene encoding gp91phox lead to the production of defective NADPH oxidase, resulting in impaired oxidative burst and inability to kill pathogens.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the defect in CGD is not related to the complement system, which is a separate component of the innate immune system.
* **Option B:** This option is incorrect because the defect in CGD is not related to the humoral immunity, which is primarily mediated by B cells and antibodies.
* **Option C:** This option is incorrect because the defect in CGD is not related to the cell-mediated immunity, which primarily involves T cells.

**Clinical Pearl / High-Yield Fact**
Patients with CGD are prone to infections with catalase-positive bacteria, such as Staphylococcus aureus, and fungi, such as Aspergillus. They may also experience skin lesions, lymphadenitis, and hepatosplenomegaly.

**Correct Answer: D.**