**Core Concept**
The ejection fraction (EF) is a measure of the heart's efficiency in pumping blood, calculated as the ratio of stroke volume to end-diastolic volume. An increase in EF indicates improved cardiac function.

**Why the Correct Answer is Right**
Since the question is incomplete, let's discuss the general concept. An increase in ejection fraction would typically lead to a decrease in end-systolic volume, as more blood is being pumped out of the heart with each contraction.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific options, it's challenging to provide detailed explanations.
**Option B:** Generally, an increase in EF might not directly relate to option B without knowing what B represents.
**Option C:** Similarly, without the context of option C, it's hard to determine its relevance.
**Option D:** The same applies to option D.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that an increased ejection fraction can be a sign of improved cardiac function, but it doesn't always translate to better clinical outcomes without considering other factors like blood pressure and overall cardiac output.

**Correct Answer:** Not provided due to incomplete question.