6．The veterinary health certificate for SVC-susceptible fish must be dated no more than ____ days prior to the date of entry to the United States．
A.A．60
B.B．30
C.C．10
D.D．7
正确答案是B
6．The veterinary health certificate for SVC-susceptible fish must be dated no more than ____ days prior to the date of entry to the United States．
A.A．60
B.B．30
C.C．10
D.D．7
正确答案是B