A force of - F$\hat{k}$   acts on O, the origin of the coordinate system. The torque about the point (1, –1) is

• A

  $F(\stackrel{\rightharpoonup }{i} +\overrightarrow{j})$

• B

  $-F(\overrightarrow{i}-\overrightarrow{j )}$

• C

  $F(\overrightarrow{i}-\overrightarrow{j})$

• D

  $-F(\stackrel{\rightharpoonup }{i} +\overrightarrow{j})$