Biologists called on urgent protection of dolphins on account of ______. A．the widespread distribution of fishing nets B．the excessive dam construction along rivers C．the rising human threat due to inconsideration D．the deteriorated and ruined coastal ecosystems
A. A．the B.the C.the D.the
【参考答案】
C 根据第三段中的“…thesix-toeight—footdolphins…neededtobeprotect......