What other adaptation could have helped koalas as they evolved from land dwellers to tree dwellers? the ability to have several offspring at one time
fur color that closely matches the eucalyptus bark color
longer hind legs that allow for faster running
better ability to communicate with their peers

Camouflage, so the answer is B. fur color that closely matches the eucalyptus bark color

Explanation:

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.