__The unit of gc is__

• A. lbm/lbf . ft/seC‚Äö√á√á
• B. lbf/lbm . ft/seC‚Äö√á√á
• C. lbm/lbf . seC‚Äö√á√á/ft
• D. lbf/lbm . seC‚Äö√á√á/ft