- 搜標(biāo)題
- 搜題干
- 搜選項(xiàng)
單項(xiàng)選擇題
有利于交替共聚的條件是（）
A、r1>1，r2<1
B、r1=1，r2>1
C、r1<1，r2<1
D、r1·r2→0
B、r1=1，r2>1
C、r1<1，r2<1
D、r1·r2→0
