Final answer:
The most appropriate initial test for a 60-year-old man presenting with nausea and epigastric pain is an upper endoscopy, as it allows direct visualization of the upper GI and can identify various conditions.
Step-by-step explanation:
For a 60-year-old man with a 2-week history of nausea and episodes of epigastric pain, when considering the most appropriate initial test, an upper endoscopy is often the first-line diagnostic procedure. This is because it allows direct visualization of the upper gastrointestinal (GI) tract, which can help identify the cause of symptoms, potentially revealing conditions like gastritis, gastroesophageal reflux disease (GERD), or peptic ulcers. It is a useful tool for diagnosing various GI problems and can also provide opportunities for biopsy if needed.
While a gastrointestinal series, CT Scan, ultrasonography, or MRI may also provide valuable information, these tests are typically considered after an initial assessment with endoscopy. Due to the man's age and symptoms, a prompt endoscopic examination is prudent to rule out serious conditions such as peptic ulcers or even malignancy, which are more common with increasing age.