There is a substantial interest in the health benefits of the consumption of high amounts of fiber in diets. A market research team is interested in the public acceptance of a new high-fiber cereal (more than 8 gm of fiber per serving) that is to be marketed. To that end, the researchers selected a random sample of subjects from one region of the country. The selected subjects were provided with two bowls of cereal. One bowl contained the new cereal and the other bowl a well-known and popular cereal. The bowls were presented in random order and subjects asked which cereal they preferred. The study was repeated independently in a second region. In region 1, of the 400 subjects, 220 perferred the new cereal; in region 2, 195 of the 300 subjects indicated a preference for the new cereal.

What is the value of the test statistic?

A. t = -2.67

B. z = -2.70

C. z = -3.84

D. z = -2.66

E. t = -2.70