Final answer:
The function showName in Python is called using showName(). This is standard syntax in Python for calling functions. So option (d) is correct.
Step-by-step explanation:
In Python, to call a function, you use the function name followed by parentheses. The parentheses are used to pass arguments to the function (if any), but in this case, the function showName doesn't take any arguments, so you simply use () to invoke it.
Option a (showName.run()) is incorrect because the run() method is not applicable to the showName function in this context. The run() method is typically used for executing a thread or a callable object, not for calling functions defined in the standard way.
Option b (open(showName)) is incorrect because the open() function is used for opening files, not for calling functions.
Option c (run showName) is not valid Python syntax. You must use the function name followed by parenthesis to invoke a function.
Therefore, the correct way to call the showName function is showName().