Both the expansion and constriction of blood vessels are the possible cause of a vascular headache.

A．all the Republicans have realized their crisis
B．the Republican Party has lost its power
C．the Republicans have to change the present situation
D．the Republicans are determined to stay away from Bush in the election

A．were inspired by the president to hold together
B．lost interest in the frequently heard content
C．disagreed with the president on his slogan
D．felt impatient with the slow speech