Which of the following condition is associated with pseudopolyp formation?

Pseudopolyps are associated with Ulcerative colitis. Other features of ulcerative colitis includes presence of erythematous, fine granular mucosal surface, in severe cases mucosa appear hemorrhagic, edematous and ulcerated. Toxic colitis or megacolon is an impoant complication. Reference: Harrison's Internal Medicine, 18th Edition, Chapter 295, Pages 2487-2489.