<prompt> Which of the following causes vasoconstriction in all vascular bedsPGE2PGF 2aPGI2TXA2  <response>: Answer- D. TXA2COX pathway is involved in the synthesis of prostaglandins and Thromoxane A2.Endothelium contains PGI2 synthase and thus forms PGI2Platelets contain TXA2 synthase and therefore synthesize TXA2Blood vessels- Thromboxane A2 TXA2 