The knee is capable of being moved up and down over the guideways form

1.	The knee is capable of being moved up and down over the guideways formed at the _____ of the column.
A.	front
B.	back
C.	can‚Äö√Ñ√∂‚àö√ë‚àö¬•t say anything
D.	none of the mentioned
Answer» B. back

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