The Following Are the Main Steps in the Generation of an Action

Multiple Choice

The following are the main steps in the generation of an action potential. 1.Sodium channels are inactivated.
2) Voltage-gated potassium channels open and potassium moves out of the cell,initiating repolarization.
3) Sodium channels regain their normal properties.
4) A graded depolarization brings an area of an excitable membrane to threshold.
5) A temporary hyperpolarization occurs.
6) Sodium channel activation occurs.
7) Sodium ions enter the cell and depolarization occurs.
The proper sequence of these events is

A) 4,6,7,3,2,5,1.
B) 4,6,7,1,2,3,5.
C) 6,7,4,1,2,3,5.
D) 2,4,6,7,1,3,5.
E) 4,2,5,6,7,3,1.