**Core Concept**
Postmortem lividity, also known as livor mortis, is the discoloration of the skin due to the pooling of blood in the dependent parts of the body after death. It is influenced by the **circulatory system** and **gravity**.

**Why the Correct Answer is Right**
Since the actual options are missing, let's consider a general scenario where postmortem lividity might not occur, such as in cases of severe **hemorrhage** or **exsanguination**, where there isn't enough blood left in the body to cause lividity.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the actual option, we can't provide a specific reason, but generally, any option that doesn't relate to a condition preventing blood from pooling wouldn't be correct.
**Option B:** Similarly, without the specific option, we can speculate that if it doesn't involve a mechanism preventing livor mortis, it's incorrect.
**Option C:** This could potentially be related to a condition affecting blood pooling, but without specifics, it's hard to assess.
**Option D:** If this option doesn't describe a scenario where lividity is prevented due to lack of blood or other factors, it would be incorrect.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that postmortem lividity can be affected by the position of the body after death and environmental factors.

**Correct Answer:** D. Severely hemorrhaged bodies