A nurse educator is briefly describing the mechanism of blood clotting to a group of nursing ...

A nurse educator is briefly describing the mechanism of blood clotting to a group of nursing students. After a review of the mechanism of blood clotting, the students have been requested to place the steps in the correct sequence.
 
  Which is the correct sequence for the mechanism of blood clotting?
  1 . Platelets break down and cause the release of thromboplastin, which interacts with certain protein factors and calcium ions to form prothrombin activator.
  2 . Prothrombin activator reacts with additional calcium ions to convert the plasma protein prothrombin to thrombin.
  3 . Threads of fibrin form a net to entrap red blood cells and platelets to form a clot, which acts like a plug in a hole and tends to draw injured edges together.
  4 . Thrombin converts the soluble plasma protein fibrinogen into insoluble threads of fibrin.
  A) 1, 2, 4, 3
  B) 2, 1, 3, 4
  C) 3, 2, 4, 1
  D) 4, 1, 2, 3