Butch Bought a Bulldozer for His Construction Business from Construction

Butch bought a bulldozer for his construction business from Construction Supply (CS) , which properly perfected its security interest in the machine. The bulldozer required repairs; Butch took it to Mike Mechanic who performed $1100 worth of repair work on it. Butch then failed to pay either CS or Mechanic, and CS appeared at Mechanic's shop to repossess the machine. As between Mechanic and CS, who gets paid first?

A) CS because it perfected its security interest.
B) CS because the bulldozer is not "consumer goods."
C) CS because it has a purchase-money security interest in the bulldozer.
D) Mechanic because he has a mechanic's lien which takes priority over the CS's security interest.
E) It is not possible to determine who wins on the facts here.