jQuery is a popular JavaScript library that simplifies HTML DOM tree traversal and manipulation, as well as event handling and animation.
To control the visibility of HTML elements, jQuery provides several methods:
(A) `.hide()`: This function makes the selected elements invisible. By default, it works by setting the CSS `display` property of the element to `none`. It can also take arguments to create an animation effect over a specified duration. The complementary function is `.show()`.
(B) `.remove()`: This function completely removes the selected elements from the DOM. They are not just hidden; they are gone.
(C) `notDisplay()`: This is not a standard jQuery function.
(D) `invisible()`: This is not a standard jQuery function.
Therefore, the jQuery function used to make an element invisible is `hide()`.