设随机变量X有期望E(X)与方差D(X)则对任意正数ε，有()
A.P(∣X-E(X)∣﹤ε)=D(X)/ε2
B.P(∣X-E(X)∣﹤ε)﹥D(X)/ε2
C.P(∣X-E(X)∣≥ε)≤1-D(X)/ε2
D.P{}∣X-E(X)∣≥ε}≤D(X)/ε2
正确答案D 
设随机变量X有期望E(X)与方差D(X)则对任意正数ε，有()
A.P(∣X-E(X)∣﹤ε)=D(X)/ε2
B.P(∣X-E(X)∣﹤ε)﹥D(X)/ε2
C.P(∣X-E(X)∣≥ε)≤1-D(X)/ε2
D.P{}∣X-E(X)∣≥ε}≤D(X)/ε2
正确答案D 