Answer to Question 1
ANS: B
Thrombin does not activate plasminogen. It does perform all of the other functions listed.
Answer to Question 2
ANS: C
Cofactors bind to their specific activated serine protease to stabilize the protease and increase its activity. One example is the binding of the cofactor Va to factor Xa, which then magnifies the activity of factor Xa to activate prothrombin.