A 37-year-old female presents with sharp pain in her right upper abdominal quadrant and right...

This symptom pattern is most consistent with cholecystitis . The gallbladder sits in the right upper quadrant , and gallbladder inflammation commonly causes RUQ pain that can radiate to the right shoulder or scapular area as referred pain. Authoritative references describe acute cholecystitis with upper right abdominal pain that spreads to the right shoulder or back , which matches this question closely. ( MSD Manuals )

From an EMT test perspective, the location and radiation pattern are the biggest clues. Appendicitis usually starts more centrally and localizes to the right lower quadrant , gastroenteritis is more associated with diffuse cramping, vomiting, and diarrhea, and diverticulitis classically causes left lower quadrant pain. That makes D. cholecystitis the best answer. ( MSD Manuals )