To call a function named "myFunction", you need to use option A, which is "myFunction()". This syntax will execute the code inside the function and return any value that is specified in the function.

Option B, "call myFunction()", is incorrect because it is not valid syntax for calling a function in most programming languages, including JavaScript.

Option C, "call function myFunction", is also incorrect because it is not valid syntax for calling a function in most programming languages, including JavaScript.

Option D, "function myFunction", is incorrect because it only declares the function, but does not actually call it. To execute the code inside the function, you need to use the function name followed by parentheses, like in option A.

Therefore, the answer is: A. myFunction()