Although external validity is a desirable quality in an ...

[ENagel]

Although external validity is a desirable quality in an experiment, it is often attained at the expense of
 
  a. generalizability.
  b. random selection.
  c. applicability.
   d. internal validity.

Question 2

The null hypothesis is
 
  a. a tentative solution to the research problem.
   b. the hypothesis that is actually statistically tested.
  c. the prediction that a negative correlation exists among the variables.
  d. all of the above.

[stano32]

Answer to Question 1

D

Answer to Question 2

B