We give you on the attached sheet full details regarding packing and markin9，which must be strictly__________．

单项选择题The products described above have been subjected to （ ） treatment of at least 80ºC for 30 minutes.

A. freeze
B. cold
C. heat
D. wash

单项选择题The above mentioned condition was caused （ ）the process of manufacturing.

A、in
B、of
C、to
D、for