This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammatory Bowel Diseases, Subject name: Medicine
Drug effective in ulcerative colitis is : 
Select and explain. 
A. 5 amino salicyclic acid (5-ASA), B. Steroids, C. Salazopyrin, D. Antibiotics
A: 5 amino salicyclic acid (5-ASA)
Answer: A: 5 amino salicyclic acid (5-ASA) 
Explanation: Ans. is 'a' 5 Amino salicylic acid