Artery to bleed in duodenal ulcer haemorrhage -: (A) Splenic artery, (B) Gastroduodenal artery, (C) Left gastric artery, (D) Sup. mesenteric artery
Answer is B. Gastro duodenal artery is the most common artery involved in duodenal ulcer hemorrhage.

Also, remember

A peptic ulcer is the most common cause of massive upper gastrointestinal bleed (Duodenal ulcers > Gastric ulcers)
Bleeding ulcers in the duodenum are usually located on the posterior surface of the duodenal bulb.