all are equal before the law and ()commits crimes shall be p

whoever 在法律面前人人平等, 无论谁犯了罪都要受到惩罚.
no matter who和whoever 都可以引导让步状语从句,no matter who可以换写成whoever
如：I'll always love you no matter who you are.
= I'll always love you whoever you are.
但whoever除了和no matter who这一样的用法之外,还可以引导名词性从句.
而no matter who没有此种用法,不能代用whoever.
而名词性从句不是独立成分,它充当主句中某一个不可缺少的成分,比如主语/宾语/表语等.
如果主句缺少名词性从句,则主句不完整.
句子中 需要一个名词性从句 作主语 因此选whoever
再问： it‘s still under discusion （）the business area，which has been ruined in the fire，should bebuilt whether where when哪一个呢，为什么帮忙一下
再答： whether 你观察一下句子的结构 （）the business area，which has been ruined in the fire，should bebuilt。 which 引导的限定性定语从句 修饰 area 可以不看 business area should be built是 完整的 句子可以改写为 whether thebusiness area，which has been ruined in the fire，should bebuilt .is still under discussion.