Which is the best choice for the tenth mission of Star Trek 2? Is it purification or salvation? Introduce them separately.

Whichever you choose won't affect the later story. After the last level of the campaign, there is a list where you can choose all the levels to play repeatedly, and all the branches can be found here. No matter what you choose to purify, you can watch the doctor finally experiment on yourself, and Z is killed by the mayor. Choose to save is to help the doctor to stop P mothership from purifying the immigrant area.