(A) f(0.5)=0.5, we cannot say here f(x) value always true Because we need to know f(x) value between
0.4≤ f(x) ≤ 0.6, and here we are getting f(x) value when x=0.5
(C)Here we know f(x) value between 0 to 0.5. But when f(x)=0.6 , x value may be ≥1
(D) Here also we cannot predict f(x) value when 0.4≤ f(x) ≤ 0.6
f(0.5)>0.5 is an inequality. So, we cannot get any exact value of x
Now for (B) Here we can see the f(x) value 0.4≤ f(x) ≤ 0.6 when x between 0 to 1
for eg: f(0.5)=0.4, where x value is 0.5
f(0.6)=0.48,where x value is 0.6
f(0.7)=0.56 , where x value is 0.7
here we are only concern about f(x) is between 0.4 and 0.6.
so, here value of x always between 0 ≤ x ≤ 1 when 0.4≤ f(x) ≤ 0.6
So, answer will be (B)