Final answer:
Mesosaurus fossils are found in regions that were once lakes and coastal bays or estuaries; these areas are colored blue to indicate their aquatic habitats. Today, these areas might be arid or desert-like but would have been coastal in the Mesosaurus era.Option C is the correct answer.
Step-by-step explanation:
The land where Mesosaurus fossils are found would have been areas that were once lakes and coastal bays or estuaries, which today could correspond to regions that are either arid or have become deserts.
The Mesosaurus was a freshwater or brackish water reptile that lived during the early Mesozoic Era, about 240 million years ago. Fossils indicate they had limbs adapted for swimming but also could walk on land. When coloring areas with these fossils based on their paleoenvironment, one would color them blue to represent their aquatic habitats.
Thus, the answer to the question, 'What is the land like where Mesosaurus fossils are found?' would most closely be represented by option C) Coastal, considering their natural habitat in ancient times. The present-day land, however, might fit options A) Arid or D) Desert if geological changes over millions of years have turned these habitats into dry landscapes.