A random sample of San Diego residents averages 1.4 children while the state as a whole averages 1.7 children. The Z score computed in this test is .78. The alpha level is .05 and the critical Z value is + or - 1.96. Therefore, the difference in the size of family...

a. is due to random chance
b. does not reflect the situation of all the people in San Diego
c. is statistically significant
d. all of the above