Final answer:
When entering a complete expression at the prompt, the system evaluates it and returns a specific output value if the expression is correct and valid. For example, entering '3 + 4' in a Python prompt would yield the output value 7.
Step-by-step explanation:
When a complete expression is entered at the prompt, the result of the evaluated expression is D. A specific output value. In most programming languages or computational contexts, the prompt is where you enter commands or expressions for evaluation. Once you input a complete expression, the system processes it and returns a result, usually displaying it directly in the console or output window.
The return value depends on the correctness of the expression and the context of its evaluation. If the expression is correctly formed according to the syntax rules of the programming language in use, and if all operations within the expression are valid, the system will produce and display a specific output value, which is the result of the computation or the operation indicated by the expression.
Here is an example:
In Python, if you type 3 + 4 at the Python prompt, it will evaluate the expression and return 7, which is the sum of the two numbers. This returned value is the output of the evaluated expression, not a new variable or the expression itself.
If there is a syntax error or other issue with the expression that prevents it from being evaluated, most systems will return an error message, not a specific output value. However, the primary expected outcome when you enter a correct expression is that it gets evaluated, and therefore the correct answer to the question is D. A specific output value.