**Core Concept**
Fat necrosis is a form of traumatic fat degeneration that occurs due to the release of lipases from damaged fat cells, leading to the formation of soaps and ultimately, calcification. This process is often seen in areas with high concentrations of adipose tissue, such as the breast and buttocks.

**Why the Correct Answer is Right**
Fat necrosis typically occurs in areas subjected to blunt trauma, such as the breast after a motor vehicle accident or a fall. The trauma leads to the release of lipases from damaged fat cells, which then catalyze the hydrolysis of triglycerides to glycerol and free fatty acids. The free fatty acids then react with calcium ions to form calcium soaps, which are visible on imaging studies as calcifications. This process is a classic example of enzymatic degradation of tissue.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because fat necrosis is not typically associated with ischemic injury, which would be more characteristic of coagulative necrosis.
**Option B:** This option is incorrect because hemorrhagic necrosis is more commonly seen in the context of infarction, such as myocardial infarction, rather than traumatic injury.
**Option C:** This option is incorrect because liquefactive necrosis is more characteristic of brain tissue after ischemic injury, such as in the context of a stroke.

**Clinical Pearl / High-Yield Fact**
It is essential to distinguish fat necrosis from malignancy on imaging studies, as both can present with calcifications. However, fat necrosis typically has a characteristic "rim sign" on ultrasound, where the calcifications are seen as a rim surrounding a fluid-filled cavity.

**Correct Answer:** D.