Which Control Flow activity should be used to evaluate a counter before executing a loop's body?

The While control flow activity is specifically designed to evaluate a specified condition before executing the body of the loop. In this context, if a counter is being used to determine how many times the loop should execute, the While activity will check the condition related to that counter prior to entering the loop.

When using a While loop, if the condition is true, the loop's body will execute, and after the execution, the condition is checked again before potentially running the loop again. This means that you maintain control over the loop execution based on the counter.

With other options, the For Each activity is used for iterating through a collection, executing the same body of code for each item. The Do While activity, on the other hand, evaluates the condition after executing the loop's body at least once. The Flow Decision activity is typically utilized to make decisions within workflows but does not inherently create looping structures. Thus, the While activity is the most fitting choice for evaluating a counter before executing a loop’s body.