With a lot of problems _____, the newly-elected headmaster is having a hard time. [ ]

A. settled

B. settling

C. to settle

D. being settled

纳税人提供应税劳务、转让无形资产或销售不动产，价格明显偏低而又无正当理由的，主管税务机关有权核定其营业额。( )