This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T., Subject name: Radiology
[{'content': 'Which is the most commonly involved muscle in cases of abdominal wall hematoma? \nSelect and explain. \nA. Rectus abdominis, B. External oblique, C. Internal abdominis, D. Transverses abdominis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans AMost commonly involved muscles - incases of traumatic hematomas - in descending order of frequency are:# Rectus abdominus (Most common).# Iliopsoas.# Thighs# Gluteal.', 'role': 'assistant'}]