Which of the following correctly represents the way to call a function named 'calculate'?

• A. calculate[]
• B. calculate()
• C. call calculate()
• D. calculate[]()

Answer: (B)

To call a function named 'calculate', you need to use parentheses to indicate that you are invoking the function. This is the established syntax in Python for executing a function. The function name followed by empty parentheses means that you are calling the function with no arguments.

Using parentheses is essential, as it distinguishes the function call from simply referencing the function’s name, which would merely point to the function object without executing it. The other options either use square brackets, which are not applicable for function calls, or use an incorrect phrase that suggests a different syntax. Thus, option B correctly follows the Python convention for function invocation.