Final answer:
The false statement about the Spanish C) Missions is that they were not affected by European diseases.
Step-by-step explanation:
The false statement about the Spanish Missions is C) The missions were not affected by European diseases.
In reality, the Native Americans living in the missions were severely affected by European diseases brought by the Spanish. These diseases, such as smallpox and measles, had a devastating impact on the Native American population, causing high mortality rates.
Furthermore, the missions were established for the purpose of converting Native Americans to Christianity (option A), were usually built near fertile land and water sources (option B), and the Native Americans were indeed forced to labor for the missions (option D).