Grandma gertrude's chocolates, a family owned business, has an opportunity to supply its product for distribution through a large coffee house. However, the coffee house chain has certian specifications regarding cacao content and it wishes to advertise the health benefits (antioxidants) of the chocolate product it sells. Past data indicate a standard deviation of 4%. If quality control inspectors wish to estimate the % cacao within 1% of the true mean with 95% confidence, how many pieces of chocolate should they sample?
A. 54
B. 36
C. 62
D. 89
E. 29