Let $C$ be a circle with radius $\sqrt { 10 }$ units and centre at the origin. Let the line $x + y = 2$ intersects the circle C at the points P and Q . Let MN be a chord of C of length 2 unit and slope - 1 . Then, a distance (in units) between the chord PQ and the chord MN is\\
(1) $3 - \sqrt { 2 }$\\
(2) $\sqrt { 2 } + 1$\\
(3) $\sqrt { 2 } - 1$\\
(4) $2 - \sqrt { 3 }$