Dr. Jordan operates a dental practice, and she would like to estimate the proportion of her patients that have dental insurance from their employers. A random sample of 110 patients found that 40 had insurance coverage. The 95% confidence level to estimate the proportion of patients with dental insurance is:

a. 0.346, 0.383

b. 0.327, 0.401

c. 0.227, 0.501

d. 0.274, 0.454