The surgeon decided to do exploratory laperatomy to patient what would be diagnosis?

45 year old male patient became to physician because of sever abdominal pain and abdominal distention with diffuse ab tenderness with anorexia ; which occur 9 days before then coming increase and sever . Before the last day the patient had been passing stool but now can’t . 9 yr ago the patient had hospitalized due to pulmonary embolism. bp 125/82,HR 123/min
Spo2 85% RR 18/min , wbc were 16500/microlit, liver function test was normal, urinalysis normal, ab ultrasonography shows free fluid in ab cavity, ab flain x _ ray shows excessive gas in GI tract ,CT and other nessecery tests are not available , the surgeon decided to do exploratory laperatomy to patient what would be diagnosis ???

A_ Intestinal obstruction
B_ mesenteric thromboembolism
C_toxic mega colon
D_ peptic ulcer perforation
E_ ischemic colitis

The patient had been mesenteric thromboembolism complicated to intestinal gangrene and 80 cm small intestine resected