Which symptom is sharp and worsens with eating in the case of gallstones?

The symptom of right upper quadrant (RUQ) pain is highly characteristic of gallstone disease, particularly when it is sharp and exacerbated by eating. This pain typically arises due to the presence of gallstones obstructing the bile ducts or causing irritation of the gallbladder, especially after the ingestion of fatty foods. When fat is digested, the gallbladder contracts to release bile for digestion, which can trigger sharp pain if a stone is present and obstructing the duct.

In contrast, hematemesis (vomiting blood) and melena (dark, tarry stools) are often associated with gastrointestinal bleeding and do not relate to gallbladder issues. Rectal pain is generally linked to conditions affecting the lower gastrointestinal tract and not typically associated with gallstones. Therefore, the specific relation of sharp RUQ pain that worsens with eating firmly identifies it as the correct symptom tied to gallstones.