Dinosaurs originated

Reptiles had overcome the evolutionary hurdles of support and reproduction that limited the amphibians. Reptiles had strong ossified skeletons supported by advanced muscular systems for body support and locomotion. Some of the largest animals ever to live were dinosaurs of the Jurassic Period. Reptiles were also capable of laying amniotic eggs, which kept the developing young moist and nourished during gestation. This allowed for the first fully terrestrial animal life cycles. Dinosaurs may have been the dominant land animals, but they were not alone. Early mammals were mostly very small herbivores or insectivores and were not in competition with the larger reptiles. Adelobasileus, a shrew-like animal, had the differentiated ear and jaw bones of a mammal and dates from the late Triassic. Thus, option B is correct and other options are wrong.