Consider the Following to Answer the Question(s) Below

Multiple Choice

Consider the following to answer the question(s) below:
National birth rates (births per 1,000) may be influenced by the average national life expectancy in years and the national literacy rate (% of population that can read and write) . Data for 49 countries were obtained and the regression results follow.
-If an additional explanatory variable was added to the model, what would happen to R2?

A) It would stay the same or increase.
B) It would always decrease.
C) It can decrease.
D) It can become negative.
E) If the coefficient of the additional variable is negative, R2 dramatically decreases.