A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at a=0.10, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?

pine tree spruce tree

sample size 40 60

mean trunk diameter, cm 36 30

population variance 165 127

A) the data does not support the conclusion that the average pine tree trunks are larger because the test value 0.96 is less than the critical value 1.28

B) the data supports the conclusion that the average pine tree trunk are larger because the test value 2.40 is greater than the critical value 1.28

C) The data supports the conclusion that the average pine tree trunk are larger because the test value 2.40 is greater than the critical value 1.65

D) the data does not support the conclusion that the average pink tree trunks are larger because the test value 30.81 is greater than the critical value 1.65