From a population of size 1,000, a random sample of 100 items is selected. the mean of the sample

a.
? must be equal to the mean of the population, if the sample is truly random.

b.
? must be 10 times larger than the mean of the population.

c.
? can be larger, smaller or equal to the mean of the population.

d.
? must be 10 times smaller than the mean of the population.