120.可动心轨辙叉道岔的垫板作业，垫板应( )

120.可动心轨辙叉道岔的垫板作业，垫板应( )

A.数量不超过l块，厚度超过6mm

B.数量超过2块，厚度不超过6mm

C.数量不超过1块，厚度不超过10mm

D.数量不超过2块，厚度不超过10mm

正确答案是A