Which tool should be used to create a new feature class for areas where a mammal weighs more than 45 kilograms?

To create a new feature class for areas where a mammal weighs more than 45 kilograms, the appropriate tool to use is the Union tool. The Union tool combines multiple input feature classes and maintains all attributes of those features. It is particularly useful when you need to gather data from overlapping areas or when you want to create a new feature class based on specific criteria, such as weight categories of mammals.

Using the Union tool allows you to input various feature classes that might represent different aspects of the habitat or populations of mammals. By performing a union operation, the resulting feature class will include all input geometries and their attributes, allowing you to filter or analyze those specifically associated with mammals weighing over 45 kilograms.

The other tools mentioned do not serve the same purpose in this scenario. The Intersect tool is used to find overlapping areas between two or more feature classes but may not retain the necessary information if the focus is only on mammals exceeding a weight threshold. The Buffer tool creates an area around a feature but does not create a new dataset based on weight attributes. The Merge tool combines multiple feature classes into one but does not perform any selection based on criteria like weight. Thus, Union is the most effective choice for creating a new feature class based on specific attributes