Answer:

The correct syntax to define a function in JavaScript is option 'B':

```javascript
function myFunction() {}
```

This syntax follows the standard JavaScript function declaration format. Let's break down the syntax and explain each part.

Function Declaration:
In JavaScript, the function declaration begins with the `function` keyword, followed by the function name. In this case, the function name is `myFunction`.

```javascript
function myFunction() {}
```

Function Name:
The function name, `myFunction`, can be any valid identifier in JavaScript. It should follow the rules for naming variables, such as not starting with a number and not containing special characters (except for underscores and dollar signs).

```javascript
function myFunction() {}
```

Function Parameters:
If the function requires any input parameters, they can be included within the parentheses after the function name. For example, `function myFunction(parameter1, parameter2) {}`.

```javascript
function myFunction(parameter1, parameter2) {}
```

In this case, the function declaration does not have any parameters, so the parentheses are empty.

Function Body:
The function body is enclosed within curly braces `{}`. It contains the code that will be executed when the function is called. In this case, since the function declaration does not have any code inside the body, it is empty.

```javascript
function myFunction() {
// Function body
}
```

Summary:
To define a function in JavaScript using the correct syntax, we use the `function` keyword followed by the function name, optional parameters within parentheses, and a function body enclosed within curly braces. Option 'B' correctly represents this syntax:

```javascript
function myFunction() {}
```

Remember that this is just one way to define a function in JavaScript, and there are other ways to accomplish the same result, such as using function expressions or arrow functions. However, the function declaration syntax shown in option 'B' is a widely used and preferred method for defining functions in JavaScript.