Which of the following is a correct way to declare a constant in JavaScript?

Declaring a constant in JavaScript is achieved using the const keyword. This denotes that the variable being declared cannot be re-assigned after its initial value is set. In the case of the provided example, const myConstant = 10; correctly creates a constant named myConstant with a value of 10.

Using const provides the benefit of ensuring that the value remains fixed, which can help prevent accidental changes to the variable later in the code. It establishes a clear intent that this particular variable is meant to remain constant throughout its scope.

The other options present different variable declaration keywords. The use of constant is not a valid JavaScript keyword; let allows for re-assignment of the variable, making it unsuitable for constants; and var is an older way of declaring variables that’s function scoped instead of block scoped, which does not inherently prevent re-assignment. Thus, these other methods do not fulfill the requirement to declare a constant.