Which of the following denotes the primary reason that the nurse inserts an indwelling urinary (Foley) catheter in a child with severe burns

A. Monitoring for a urinary tract infection.
B. Measuring urine output accurately.
C. Preventing urinary retention.
D. Assessing urine specific gravity.

医学上重要的质粒有（）

A.R质粒

B.F质粒

C.Col质粒

D.毒力质粒

E.r质粒