Which of the following statements is true?
The normal, healthy vagina cleanses itself.

Douching decreases the risk of infections.

The vagina normally has an alkaline environment.

Douching should be done monthly.

The normal, healthy vagina cleanses itself.

Explanation:

The vagina will clean itself inside your body with natural vaginal secretions (discharge).

hope this helps :)

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.