Your friend decides to flip a coin repeatedly to analyze whether the probability of a head on each flip is 1/2. He flips the coin 20 times and observes a head 12 times. He concludes that the probability of a head for this coin is 12/20=0.60 and the coin is not balanced. What is a correct interpretation?

A. Probability doesn't prove anything about the coin because probability is subjective
B. A coin is balanced as long as the probability of each outcome is closer to 0.5 than it is to 1 or 0.
C. Environmental conditions such as temperature and humidity can cause the results of flipping a balanced coin to be skewed and thus appear unbalanced.
D. In the short run, the proportion of a given outcome can fluctuate a lot. A long run of observations is needed to accurately calculate the probability of flipping heads.