One hundred tomato plants were randomly selected from a large garden, and a 90% confidence interval was computed to determine the true proportion of plants that produce usable tomatoes. The interval is 0.86 to 0.92. What would happen to the width of the confidence interval if the sample size was quadrupled?
a. The width of the interval would quadruple.
b. The width of the interval would double.
c. The interval would be one-fourth the original width.
d. The interval would be half the original width.