Which JavaScript method can be used to select an element by its ID?

The method getElementById is specifically designed to select a single HTML element by its unique ID attribute. In a standard web document, each ID must be unique, making getElementById highly efficient for targeting a specific element directly. This method returns the element as an object, allowing developers to manipulate it easily (changing styles, text, attributes, etc.).

While querySelector can also be used to select elements, it is more versatile as it allows selection through any valid CSS selector, including ID selectors. However, when focusing on selecting an element explicitly by its ID, getElementById is undoubtedly the more straightforward and specialized option for this purpose.

getElementsByClassName targets multiple elements that share the same class name, returning a live HTMLCollection, which is not suitable for ID selection. selectElement is not a recognized method in JavaScript for selecting elements, making it an incorrect option. Thus, in contexts where the goal is to select an element by ID specifically, getElementById is the preferred choice.