A linear function has the same slope everywhere.
The first relation, f(2)≤f(3), says the slope is positive or zero.
The second relation, f(4)≥f(5), says the slope is negative or zero.
The only way both relations can be true is if the slope of the line is zero. Since f(6) = 10, the function must be ...
... f(x) = 10
making the only true statement ...
... D. f(0) = 10