The data are from Charles Darwin’s study of cross- and self -fertilization. Pairs of seedlings of the same age, one produced by cross-fertilization and the other by self-fertilization, were grown together so that members of each pair were reared under nearly identical conditions. The aim was to demonstrate the greater vigor of the cross-fertilized plants. The data given in pairs are the heights ofeach plant (in inches) after a fixed period of time. Cross (X1)

23.5

12.0

21.0

22.0

19.1

21.5

22.1

20.4

18.3

21.6

23.3

Self (X2)

17.4

20.4

20.0

20.0

18.4

18.6

18.6

15.3

16.5

18.0

16.3

Using d = x1- x2, carry out the test using a 0.05 level of significance.

The conclusion is:

Group of answer choices

Cross-fertilized plants have the same vigor as the self-fertilized plants.

Cross-fertilized plants do not have greater vigor than self-fertilized plants

Cross-fertilized plants have greater vigor than self-fertilized plants

Cross-fertilized plants have lesser vigor than the self-fertilized plants