题目内容：
在1977年，中国进出口总额还不到150亿美元，仅占世界贸易总额的0.6%。
A In 1977, the total sum of Chinese imports and exports was less than $15 billion, put ChB In 1977, the sum total of Chinese imports and exports was less than $15 billion, puttin
C In 1977, the sum total of Chinese imports and exports was less than $150 billion, putti
D In 1977, the total sum of Chinese imports and exports was less than $150 billion, putti
参考答案：