The example that Sourwood changes colors before other species do illustrate that the timing of color change______.

A．She is very happy to obey the rules.
B．She is very interested in the rules.
C．She is irritated by so many rules.
D．She is sorry for the rules.

A．He was asked to leads group of inexperienced carets there.
B．It was the first cave that he had ever visited.
C．Clearly marked trails made it easy to explore.
D．lie hoped to make a discovery.