Which sentence makes the BEST topic sentence?

This sentence introduces a topic (housing for animals in zoos) that could be explored in a passage. Choices Giant pandas live solitary lives and roam large tracks of land looking for food. and Natural borders, such as moats and rock walls, can help make animals feel at home. would work best as supporting details. Choice Sadly, it seems many zoos do not have the funding to build these large habitats. belongs at the end of a passage because it contains references to previously discussed details.