Question: A 25 year old patient with history of long standing constipation was seen at regul OPD for severe pain, tenesmus and small amount of bright red bleeding per recti passage of hard and dry stool. It is difficult to do digital per rectal examination d pain. What is the most likely diagnosis? A. Perianal abscess B. Perianal fistula C. Anal fissure D. Haemorrhoids