Final answer:
In the absence of a definitive answer within the film 'Avatar', it can be speculated that Grace moved the team to Site 26 because of the Na'vi presence, rich flora and fauna, and a potentially safer location.
Step-by-step explanation:
The question pertains to why Grace moves the team to Site 26 in the film Avatar. While the options provided A) Rich flora and fauna, B) Na'vi presence, C) Unobtanium deposits, and D) Safer location, are potential factors for such a move, the actual reason for the move is not clearly provided. Considering the context of the movie, the actual agenda behind Grace's decision could encompass a blend of scientific curiosity about Pandora's Na'vi presence and rich flora and fauna, along with practical considerations regarding the site's safer location. Without a definitive answer provided within the film, one can speculate that a combination of these factors led to Grace's decision.