一个偏僻的岛屿上的鸟类数量在一年中保持相对恒定的大小。以下哪一个最有可能描述出生率和死亡率? An isolated bird population on a remote island remains at a relatively constant size year after year. Which of the following most likely describes the birthrate and the death rate for this population?
A.
Birthrate is significantly greater than death rate. 出生率显著高于死亡率。
B.
Birthrate and death rate are close to equal. 出生率和死亡率接近相等。
C.
Birthrate is significantly lower than death rate. 出生率明显低于死亡率。
D.
Birthrate and death rate are both zero. 出生率和死亡率都为零。