If the shortest distance between the straight lines 3(x - 1) = 6(y - 2) = 2(z - 1) and 4(x - 2) = 2(y - λ) = (z - 3), λ ∈ R is 1/√38, then the integral value of λ is equal to :
a. 3
b. 2
c. 5
d. -1