Which diagnostic test is most commonly used to confirm the diagnosis of gastritis?

Correct Answer: B

Rationale: Endoscopy with biopsy is the gold standard for diagnosing gastritis as it allows direct visualization of the stomach lining and histological confirmation of inflammation or H. pylori infection. Barium swallow is less specific and used more for structural abnormalities. Abdominal ultrasound assesses organs like the liver or gallbladder, not gastritis. Stool culture is irrelevant unless checking for H. pylori antigen, but it's not the primary method.

Correct Answer: A

Rationale: The digestive system breaks down food into fatty acids and glycerol, and the circulatory system transports these to cells for fat synthesis. Excretory removes waste, not nutrients. Immune and muscular and reproductive systems are unrelated to fat synthesis.

Correct Answer: C

Rationale: The digestive system processes food into nutrients for the body, making 'food-processing system' correct. Breathing relates to the respiratory system, nerves to the nervous system, and blood transport to the circulatory system.

Correct Answer: B

Rationale: The liver , stomach , and pancreas produce digestive juices (bile, gastric juice, pancreatic enzymes), but kidneys filter blood for urine, not digestive juices, making B correct.

Correct Answer: B

Rationale: Pepsin, a protease, breaks down proteins in meat, reducing its mass, making B correct; bile emulsifies, maltose is a sugar, and amylase digests starch.