The Principle Which Guides the Framing of a Null Hypothesis

The principle which guides the framing of a null hypothesis is:

A) one either rejects or accepts the null hypothesis on the basis of the evidence at hand
B) a null hypothesis may be rejected but can never be accepted
C) one must always reject the null hypothesis unless the evidence is convincingly (determined by the a level) to the contrary
D) one must always accept the null hypothesis unless the evidence is convincingly (determined by the a level) to the contrary
E) there is no guiding scientific principle and the analyst should frame them as he or she sees fit