The needle beam method of tunnelling
(i) Is suitable for soils in which roof can stand for few minutes without support
(ii) Is suitable for brick lining
(iii) Is suitable for concrete lining
(iv) Requires large number of trench jacks
A. Only (i) is correct
B. (i), (ii) and (iv) are correct
C. (i), (iii) and (iv) are correct
D. (i) and (ii) are correct
Answer: Option B

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