The correct sequence of these operations in tunnel construction is______________?

Consider the following operations :
1. Drilling
2. Blasting
3. Mucking
4. Placing steel
5. Placing concrete
A. 1,2,4,3,5
B. 1,3,2,4,5
C. 1,2,3,4,5
D. 1,3,4,2,5