In the process of freeze drying, a dense cell suspension is placed in small vials and is frozen at

In the process of freeze drying, a dense cell suspension is placed in

1.	In the process of freeze drying, a dense cell suspension is placed in small vials and is frozen at
A.	-60 to -78°C
B.	-20 to -30°C
C.	-30 to -48°C
D.	-48 to -58°C
Answer» B. -20 to -30°C