Which of the following commands creates a function in Bash that outputs the sum of two

numbers?

A.
function sumitup { echo $(($1 + $2)) ; }

B.
command sumitup { echo $(($1 + $2)) ; }

C.
function sumitup { echo $1 + $2 ; }

D.
method sumitup { echo $1 + $2 ; }

E.
command sumitup { echo $1 + $2 ; }

Explanation: