The p-value of a test of significance is

Select one:

a.the probability, assuming the null hypothesis is false, that the test statistic will take a value at least as extreme as that actually observed.

b.the probability, assuming the null hypothesis is true, that the test statistic will take a value at least as extreme as that actually observed.

c.the probability that the null hypothesis is false.

d.the probability that the null hypothesis is true.