The statement that is true for all of the organisms shown (an ameba, a rabbit, a human, and a tree) is:

They are all made up of cells.

Here's why:

* Ameba: An ameba is a single-celled organism.

* Rabbit, Human: Rabbits and humans are multicellular organisms, meaning they are made up of many cells.

* Tree: Trees are also multicellular organisms, with specialized cells forming tissues and organs.

Let me know if you'd like to explore other characteristics of these organisms!