Which construct allows for executing a block of statements while certain conditions remain true?

The "Do While" construct is designed specifically for executing a block of statements repeatedly as long as a specified condition remains true. This repeated execution continues to occur until the condition evaluates to false, allowing for dynamic control based on the changing state of program variables or inputs.

This construct is particularly useful in scenarios where the exact number of iterations is not known beforehand and is dependent on runtime conditions. For instance, it can be employed to continually prompt a user for input until they provide a specific response, or to process items in a list until all items have been handled.

In contrast, the other constructs do not serve this purpose. The "Case Statement" allows for branching logic based on the value of an expression, not for repetition. The "If - Then - Else" statement is used for conditional execution of statements, but it does not inherently support looping. The "Sequence" construct pertains to the order in which statements are executed but does not involve any conditions for repetition.

Thus, the "Do While" construct is aptly suited for scenarios requiring repeated execution under condition-based circumstances.