8.A population is composed of 5 numbers: 2, 4, 6, 8, 10. Let μ and σ denote mean and standard deviation of the population, and denote mean and standard deviation of the sample mnean from the population. Which of the following statement is the most correct one? (A)μ=6,σ=3.16;(B).=6,=3.16；(C).=6,=283；(D).μ=6,σ=2.83；(E)=μ,σ = 3.16.