We Sampled 100 Men and 100 Women and Asked: ʺDo

Multiple Choice

We sampled 100 men and 100 women and asked: ʺDo you think the environment is a major concern?ʺ Of those sampled, 67 women and 53 men responded that they believed it is. For the
Confidence interval procedure to work properly, what additional assumptions must be satisfied?

A) The population variances are equal.
B) Both samples were randomly and independently selected from their respective populations.
C) Both populations have approximate normal distributions.
D) All of the above are necessary.