The absolute minimum value, of the function $$f(x) = |x^2 - x + 1| + [x^2 - x + 1]$$, where $$[t]$$ denotes the greatest integer function, in the interval $$[-1, 2]$$, is

A

$$\dfrac{3}{2}$$

B

$$\dfrac{1}{4}$$

C

$$\dfrac{5}{4}$$

D

$$\dfrac{3}{4}$$