**Core Concept**
The patient presents with **hematemesis** and **melena**, indicating upper gastrointestinal bleeding. An upper GI endoscopy was performed but did not reveal any significant findings. The recurrence of bleeding suggests the need for further investigation to identify the source of bleeding.

**Why the Correct Answer is Right**
Given the lack of findings on upper GI endoscopy and the recurrence of bleeding, the next step is to investigate the small intestine as a potential source of bleeding. This can be achieved through techniques such as **video capsule endoscopy** or **push enteroscopy**, which are designed to visualize the small bowel.

**Why Each Wrong Option is Incorrect**
**Option A:** This choice is not provided, so we cannot assess its accuracy.
**Option B:** Similarly, without the option text, we cannot evaluate its correctness.
**Option C:** Assuming this might involve repeating an upper GI endoscopy, it would be inappropriate given that the initial endoscopy was recently performed and yielded no significant findings.
**Option D:** Without the text, we cannot comment on its validity.

**Clinical Pearl / High-Yield Fact**
In cases of obscure gastrointestinal bleeding where upper and lower endoscopy do not reveal a source, **video capsule endoscopy** is a valuable tool for visualizing the small intestine, which can be a common site for bleeding lesions.

**Correct Answer:** D. Video Capsule Endoscopy.