Consider the lines L1 and L₂ given by
L₁ = x-1/2 = y-3/1 = z-2/2
L₂ = x-2/1 = y-2/2 = z-3/3
A line L₃ having direction ratios 1, –1, –2, intersects L₁ and L₂ at the points P and Q respectively. Then the length of line segment PQ is

a. 2√6
b. 3√2
c. 4√3
d. 4