根据下面资料，回答36-39题
Some farmers in California are having a hard time picking their crops．There are not enough workers to help them with the harvest．
One farmer used to grow peaches (桃子), but will soon grow almonds (杏仁) instead．Peaches require more labor to harvest．They are easy to be damaged and need careful hand picking．He is now removing his peach trees．Then he will plant almond trees in their places． Almonds are harvested differently．It does not take as many workers to pick them because a machine shakes the almond trees．
The nuts fall on the ground and then are gathered up．The farmer does not have to hire many workers．
Some farmers think there are two reasons why they can' t find enough farm workers．One reason is that there are a lot of well-paid construction jobs in the are
A．Many people are taking these jobs instead of picking fruit．The other reason is that it has become more difficult for workers to come from Mexico into
California．Fewer workers are allowed to get into the country to work on the fruit farms．To settle the problem, farmers hope the government might allow these workers to work as guests．That would help workers provide for their family and help farmers harvest their crops．When the harvest season is over they' ll go back home．Farmers say that unless things change, more fruits will come from other countries．
This is because labor is cheaper in those countries than in the United States．
What problem do some farmers have
A.They have no workers to remove fruit trees
B.There is little land for growing fruit
C.Their crops were badly damaged last year
D.It' s difficult to harvest their crops