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單項(xiàng)選擇題

Damaged bulkheads often take a permanent set which is independent of the panting or bulge caused by water pressure. To control this,you should().

A.install shoring so the shoring supports the damaged bulkheads without pushing on them
B.install shoring so that it pushes on the damaged bulkhead while supporting it
C.use jacks or chain falls to remove the set before installing shores
D.place sandbags by the bulkhead without installing shores

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