Greg and Mary are testing whether fraternity members or sorority members have higher grade point averages. Greg's sample consists of 45 fraternity members and Mary's sample consists of 13 sorority members. They will be calculating an independent-samplest-test to analyze their results. When it comes to their pooled estimate of population variance (S²_pooled), which of the following statements is accurate?

a. S²_pooledwill be much closer to Greg's sample variability (S²_fraternity) than Mary's (S²_sorority)

b. S²_pooledwill be slightly closer to Greg's sample variability (S²_fraternity) than Mary's (S²_sorority)

c. S²_pooledwill be the average of Greg's sample variability (S²_fraternity) and Mary's (S²_sorority)

d. S²_pooledwill be much closer to Mary's sample variability (S²_sorority) than Greg's (S²_fraternity)