The function below may be invoked how?:

The correct option indicates that the function can be invoked with either no argument or one argument. This flexibility typically suggests that the function is designed to handle a default parameter. When a function defines a parameter but does not require it (i.e., it has a default value), it can be called without providing an argument, as the default value will be used instead. If an argument is passed during the function call, that argument will override the default value.

For example, consider the following function:

def example_function(param=10):

print(param)

In this case, if you call example_function(), it will print 10, utilizing the default parameter. Conversely, calling example_function(5) will print 5, demonstrating that the function can accept one argument as well.

This setup is common in Python programming, allowing for more versatile function calls. The other options imply stricter calling conventions, which do not account for the use of default parameters and thus would not appropriately describe the function's invocation capabilities.