大全281their 指代

242. Even their most ardent champions concede that no less than a technical or scientific breakthrough is necessary before solar cells can meet the goal of providing one percent of the nation’s energy needs.
    

(A) that no less than a technical or scientific breakthrough is necessary

(B) that nothing other than a technical or scientific breakthrough is needed

(C) that a technical or scientific breakthrough is necessary

(D) the necessity for an occurrence of a technical or scientific breakthrough（C）

(E) the necessity for a technical or scientific breakthrough occurring

Even their most ardent champions concede that a technical or scientific breakthrough is necessary before solar cells can meet the goal of providing one percent of the nation’s energy needs.

即使他们的最热情的拥护者承认一个技术的或者是科学的突破是必要的，在大阳细胞能够符合提供1%的国家所需的能量之前。

请问their指的是什么，是solar cells吗，这句话有点不明白，能给讲一下吗？？

为什么句首出现了Even呢，觉得句意很别扭？？

their= solar cells'

就算是它们最热情的支持者也承认要用太阳能电池提供1%的国内能需求还要科技进步（的支撑）。

嘲笑自已，居然还太阳细胞呢，笨。

记住了，太阳能电池。问题解决啰。

谢谢。