Hi what does this question and what is the best possible answer?

Which of the following statements is true about a posterior distribution over possible parameter values:

Select one:

a.It represents the credence the researcher gives to possible parameter values before observing the new data.

b.It represents the credence the researcher gives to possible parameter values after observing the new data.

c.It represents a null hypothesis, not an alternative hypothesis.

d.It represents a sampling distribution of the parameter values.