A television newscaster from a 24-hour news station wants to estimate the number of hours per day its viewers watch programming on this channel. The newscaster randomly selects 100 viewers and asks them how many hours per day they watch this station. The newscaster constructs an 85% confidence interval for the true mean number of hours viewers watch this station.

Which of the following would decrease the margin of error?

A. using a sample of size 50
B. using a sample of size 200
C. constructing a 90% confidence interval
D. constructing a 95% confidence interval