Changes that occur naturally in the subjects, over time could ...

[Yolanda]

Changes that occur naturally in the subjects, over time could result in the confound of:
 
  a. history.
  b. maturation.
  c. regression to the mean.
  d. diffusion of treatment.

Question 2

Internal validity is:
 
  a. the extent to which the results of an experiment can be attributed to the manipulation of the dependent variable, rather than to some confounding variable.
 b. the extent to which the results of an experiment can be attributed to the manipulation of the independent variable, rather than to some confounding variable.
 c. the extent to which the results of an experiment can be generalized.
  d. both b and c

[debra928]

Answer to Question 1

b

Answer to Question 2

b

[Yolanda]

Wow, this really help

[bimper21]

YES! Correct, THANKS for helping me on my review