答案：C.
解釋：此題考查虛擬語氣.
1. 固定句型It is necessary that..., It is suggested that...和It is an order that...的that從句中,都要that從句使用虛擬語氣,其變化規(guī)律為：that從句的謂語動詞由“should + 動詞原形”構(gòu)成,且should可以省略.
所以如果答案是ABD的話,則后面的that從句必須改成：
that we (should) make contact with the company.
由此排除ABD.
2. 固定句型It is time that...中的that從句也必須使用虛擬語氣.
其構(gòu)成是：that從句的謂語由“should + 動詞原形”構(gòu)成,此時should不能省略；
或that從句使用一般過去時,即其謂語動詞改成過去式（如果是be動詞,則一律改成were）.
而題中的從句that we made contact with the company剛好使用了一般過去時,所以答案C為正解,當(dāng)然也可以寫成that we should make contact with the company.