(d) coincident
The equations of the given lines are
Thus, the two lines are parallel to the vector and pass through the points (0, 0, 0) and (1, 2, 3).
Now,
Since, the distance between the two parallel lines is 0, the given two lines are coincident lines.
Disclaimer: The answer given in the book is incorrect. This solution is created according to the question given in the book.