If a geologist found preserved mud cracks, he or she could conclude that the environment in which they formed . a. was once covered in wet mud b. was once covered by a glacier c. was the site of a mass extinction event d. has been subjected to a major climate change event

A. was once covered in wet mud

Explanation:

The presence of preserved mud cracks indicates the region was once covered in wet mud, the wet mud sticks for a period of time. Mud cracks are known to be sedimentary in nature

A

It was once covered in wet mud.

Explanation:

The presence of mud cracks in that environment shows that the environment was once covered in water before the water dried out. Every other options do not support the formation of a mud crack. Mud cracks are sedimentary formations formed as a result of dried out muds, it is also known as desiccation crack or sun crack.