Freshwater lobe-finned fish may be the direct ancestors of terrestrial terapods. A. Rhipidistian crossopterygian had features such as primitive lungs and thick fins that could have helped it survive dry periods. B. During the Devonian, the number of bones increased in the fins of rhipidistians, improving such animals' ability to swim and move over land. C. Shortly after the earliest tetrapods developed lungs, plants and other animals began to flourish on land. D. By the Devonian period, lobe-finned fish preferred freshwater habitats to life in the ocean. E. A drier climate and new sources of food on land may have encouraged the lobe-finned fish's move to a terrestrial existence. F. Early tetrapods remained closely connected to water, but several of their body structures were adapted for life on land.