A 62-year-old man with a history of cirrhosis and chronic hepatitis B presents for surveillance imaging. A CT abdomen is performed and a 3 cm arterially enhancing lesion with delayed washout is identified in the posterolateral region of the liver. The lesion is located in the structure marked **A** (Couinaud classification). Based on the segmental location and imaging characteristics, which of the following segments is MOST likely involved?