Consider the following code snippet:public static int sum$($int n$)\{$ if $($n $==0)\{$ return $0$; $\}$ else $\{$ return n $+$ sum$($n $-1)$; $\}\}$What does this code calculate? $5$ a$.$The factorial of nb$.$The absolute value of nc$.$The sum of natural numbers from $1$ to nd$.$The remainder when n is divided by $2$