单选题
In a certain animal population, for each of the first 3 months of life, the probability that an animal will die during that month is 
【正确答案】
B
【答案解析】[解析] 因在前3个月中每个月的死亡概率都为0.1，所以出生一个月后生存下来200(1-0.1)个；同理出生两个月后存活下来200(1-0.1)2，第三个月为200(1-0.1)3=146个。