整粒大豆蛋白质的消化率只有60％，加工成豆腐后可提高至90％以上，其原因主要是加工过程去除了大豆中的（）

A.钙

B.寡糖

C.皂甙

D.纤维素

E.植物红细胞凝集素

As there were not enough chairs in the park, they had to sit on the _________. [ ]

A. ground

B. earth

C. land

D. field