Consider the algorithm:

Algorithm

Input: A natural number n

$(1)$ let c :$=1$

$(2)$ let i :$=0$

$(3)$ repeat

$($a$)$ let i :$=$ i $+1$

$($b$)$ let c :$=$ c $$ i

$(4)$ until i $=$ n

$(5)$ return c

What does the algorithm return when the input is n $=3?$

What does the algorithm return when the input is n $=4?$

What does the algorithm return when the input is n $=6?$

What does the algorithm return when the input is n $=7?$

What does the algorithm return $?$

$$ A$.(23)$n

$$ B$.$ The product of the first n natural numbers.

$$ C$.$ The remainder of the division of n by $6.$

$$ D$.2$n

$$ E$.$ The greatest common divisor of $2$ and n

$$ F$.$ The sum of the first n natural numbers.