关于2010高考英语全国1卷的阅读问题DuringthedriermonthsbetweenDecemberandMarchhoatzinsflyabouttheforestingroupsof20to30birds,butinApril,whentherainyseasonbegins,theycollecttogetherinsmallerlivingunitsof

Question

关于2010高考英语全国1卷的阅读问题
During the drier months between December and March hoatzins fly about the forest in groups of 20 to 30 birds, but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.
Why do hoatzins collect together in smaller groups when the rainy season comes?
A．To find more food.
B．To protect themselves better.
C．To keep themselves warm.
D．To produce their young.
为什么选D
谢谢!

Answer 1

but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.
producing purposes 指的就是生育过程啊,produce 是生育,产仔的意思