Final answer:
The correct properties of the standard normal distribution are that it has a symmetrical distribution with a mean of zero and a variance of one.
Step-by-step explanation:
The properties associated with sampling from normally distributed populations are that the distribution is symmetrical, the mean of the z-values is zero, and the variance of the z-values is one. Therefore, the correct answer is (a) Symmetrical distribution, Mean of zero, Variance of one. This describes the standard normal distribution, which is a special case of the normal distribution. The standard normal distribution is used in statistics to standardize scores from different normal distributions so that they can be compared on a common scale.