问题如下：
Given a certain binomial random variable x, the number of total trials is 10. If the probability of x successes in 10 trials is all 0.5, the binomial distribution is most likely to be:
选项：
A. asymmetric
B. skewed.
C. symmetric.
解释：
C is correct. The only way for a binomial distribution to be symmetric is that the probability of x successes in all trials equals 0.50.
这道题是什么意思呢。
