Multiple choice question about sampling distribution

The sampling distribution of a sample mean for a random sample size of 100 describes (more than one answer can apply)...

a) how sample means tend to vary from random sample to random sample of size 100

b)how observations tend to vary from person to person in a random sample of size 100

c) how the data from a sample of 100 looks like the population distribution

d)how the standard deviation varies among random samples of size 100

Also, how you came to that conclusion

Re: Multiple choice question about sampling distribution

This is a definition. What do you think from your notes?