Yosemite National Park has the best collection of native plants. ______, it contains a great number of trees and flowers from overseas.

A．In addition

B．In return

C．In reward

D．In reality

润滑油温升高的原因不包括（）。

A、油质不纯

B、油管或油路堵塞

C、破碎机研套

D、冷却器堵