Which method is commonly used to add an element at the end of an array in JavaScript?

The method commonly used to add an element at the end of an array in JavaScript is the push() method. This method modifies the original array by appending the specified element(s) to the end. For example, if you have an array called myArray and you want to add a new element like 5, you would call myArray.push(5);, which would result in 5 being added as the last element of the array.

The function is versatile and can also accept multiple arguments, allowing you to add multiple elements at once. When you use push(), it returns the new length of the array after the elements have been added, which is helpful for confirming that the operation was successful.

In contrast, the other methods mentioned do not exist in JavaScript for the purpose of adding elements to an array. For instance, add(), append(), and insert() are not recognized as valid array methods in JavaScript, which is why they are not suitable options for this operation.