Which of the following would be an example of a variable in a microflow?

A variable in a microflow in Mendix refers to a placeholder used to store data that can be manipulated during the execution of the flow. In this context, the correct answer, which identifies a variable, is significant because it represents a specific instance of an object type within your application.

The variable named $Customer is indicative of a single customer entity from the database, and it can hold values that are specific to that customer, such as their ID, name, email address, and other attributes. This allows you to process customer-related data effectively as you perform operations within the microflow.

The other examples provided may refer to system-defined or context-specific variables or identifiers rather than instances of objects which you can manipulate directly in a microflow. For instance, $Transaction may represent a transaction context, $OrderDetails could refer to details about an order, and the term $Result suggests an output from a microflow rather than a variable you can modify within the flow.