there are twenty people in the medical team,___

作为定语从句，第二个应该是：which includes three nurses，另外前面不加逗号。第一个是省略了are的独立主格结构。

只能用前面的，后面的错。因为后面的是个从句形式但没有谓语不完整

应该是 three nurses included 或者including three nurses.
而which including three nurses 是宾语从句，宾语从句是一个句子，必须有主谓，而including 不是谓语动词，只能将其换成includes 才对。