**Core Concept**
Curshmann's spirals are a characteristic histopathological feature seen in certain conditions affecting the lung parenchyma. They are formed due to the accumulation of fibrin and other debris in the alveoli, leading to the formation of spiral or scroll-like structures.

**Why the Correct Answer is Right**
Curshmann's spirals are typically seen in the context of alveolar hemorrhage, which can occur due to various causes such as vasculitis, connective tissue disease, or pulmonary embolism. The presence of fibrin and other debris in the alveoli leads to the formation of these characteristic spiral structures. This process is thought to be mediated by the activation of the coagulation cascade and the subsequent deposition of fibrin.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Curshmann's spirals are not typically seen in conditions affecting the bronchi or bronchioles.
**Option B:** This option is incorrect because while Curshmann's spirals can be seen in conditions affecting the lung parenchyma, they are not a characteristic feature of pulmonary edema.
**Option C:** This option is incorrect because Curshmann's spirals are not typically seen in conditions affecting the pleura.

**Clinical Pearl / High-Yield Fact**
Curshmann's spirals are a classic histopathological feature of pulmonary vasculitis, particularly in conditions such as granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (EGPA).

**Correct Answer:** D.