[单选题]

When checking zinc plates in the refrigerating system condenser, you should
A．paint and insulate the plates to prevent corrosion
B．renew the plates at each inspection
C．replace the zincs if deteriorated by 50%
D．file the plates to change the negative value

When checking zinc plates in the refrigerating system condenser, you shouldA．paint and insulate the plates to prevent corrosionB．renew the plates at each inspectionC．replace the zincs if deteriorated by 50%D．file the plates to change the negative value