According to Plumptre, the region over which a dung-pile census is carried out should be
A.small enough. B.well protected. C.carefully monitored. D.large enough.正确答案D
According to Plumptre, the region over which a dung-pile census is carried out should be
A.small enough. B.well protected. C.carefully monitored. D.large enough.正确答案D