If D is distance between centres of two parallel track of gauge G , then, total length of cross-over (from the point of commencement to the point of termination) with an intermediate straight portion and N crossing, is given by

If D is distance between centres of two parallel track of gauge G , th

1.	If D is distance between centres of two parallel track of gauge G , then, total length of cross-over (from the point of commencement to the point of termination) with an intermediate straight portion and N crossing, is given by
A.	DN + G ( N + 1 + N 2 )
B.	DN + G ( 2N + 1 + N 2 )
C.	DN + G ( 3N + 1 + N 2 )
D.	DN + G ( 4N + l + N 2 )
Answer» D. DN + G ( 4N + l + N 2 )