单选题 Our new contractor suggested that the full amount of the purchase ______ along with the proper invoices.

A、 were sent
B、 send
C、 sent
D、 be sent

【正确答案】 D

【答案解析】[解析] 语法：动词形态
1．提案、忠告、主张、要求等动词和that从句连接时，that从句的结构为“主语+(should)+动词原形”，should经常被省略。
2．主语the full amount，作为被邮寄的对象，应使用被动语态(should) be sent。因此D为正确选项。