**Core Concept**
The question is testing the understanding of the respiratory work during quiet breathing. The respiratory muscles, particularly the diaphragm, perform work to expand the lungs and maintain a normal tidal volume. The maximum work is done during the inspiratory phase, specifically during the initial rapid inflation of the lungs.

**Why the Correct Answer is Right**
The maximum work is done during the initial rapid inflation of the lungs due to the large pressure difference between the intrapulmonary pressure and the atmospheric pressure. This pressure difference is necessary to rapidly expand the lungs and increase the lung volume. The diaphragm and other inspiratory muscles contract to generate this pressure difference, resulting in the maximum work being done during this phase.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the work done during the expiratory phase is significantly less than during the inspiratory phase. The expiratory muscles, such as the internal intercostal muscles, contract to slow down the lung deflation, but the pressure difference is much smaller compared to the inspiratory phase.

**Option B:** This option is incorrect because the work done during the passive expiration is minimal. Passive expiration occurs when the diaphragm relaxes and the lung deflates due to the elastic recoil of the lungs and chest wall.

**Option C:** This option is incorrect because the work done during the inspiratory effort against a closed airway (e.g., during straining or forced inhalation) is much greater than during quiet breathing. During quiet breathing, the airway resistance is minimal, and the work is mainly done by the diaphragm and other inspiratory muscles.

**Clinical Pearl / High-Yield Fact**
Remember that the maximum work during quiet breathing is done during the initial rapid inflation of the lungs, which is primarily due to the large pressure difference between the intrapulmonary pressure and the atmospheric pressure.

**Correct Answer: C. During the initial rapid inflation of the lungs.