单选题 Our earth is full of sound because it is full of ______ like trucks rolling along the highway or jets climbing into the sky.

【正确答案】 B

【答案解析】[考点] 词义辨析。 [解析] travel旅行；motion运动；construction建造。由后半句trucks rolling和jets climbing可推知答案为B，其余选项均不符句意。