我们党要始终成为时代先锋、民族脊梁，始终成为马克思主义执政党，自身必须始终过硬。

我们党要始终成为时代先锋、民族脊梁，始终成为马克思主义执政党，自身必须始终过硬。
A.To remain the vanguard of the times， the backbone of the nation， and a Marxist governing party， our Party must always hold itself to the highest standards.
B.To remain the vanguards of the times， the backbones of the nation， and a Marxist governing party， our Party must always hold itself to the highest standards.
C.To remain the vanguard of the time， the backbone of the nation， and a Marxist governing party， our Party must always hold itself to the highest standards.
正确答案：To remain the vanguard of the times， the backbone of the nation， and a Marxist governing party， our Party must always hold itself to the highest standards.