ATP-sensitive potassium channel?

  A.  In smooth muscle cells surrounding an arteriole serving a region of the body that has just recently had very high levels of cellular activity, the potassium conductance of the ATP-sensitive potassium channels in the plasma membranes of these smooth muscle cells will be very high.

  B.  The channel is a spanning protein with a receptor site for ATP located on an extracellular region of the protein.

  C.  When blood plasma levels of glucose are very high, the potassium conductance of the ATP-sensitive potassium channels in the plasma membranes of beta-islet cells will be very high.