设f(x)={1,0,∣x∣≤1,∣x∣>1,则f{f[f(x)]}等于( )。01{1,0,∣x∣≤1,∣x∣>1f(x)={0,1,∣x∣≤1,∣x∣>1A0B1正确答案C{1,0,∣x∣≤1,∣x∣>1Df(x)={0,1,∣x∣≤1,∣x∣>1