Which three options can the developer invoke for this function to get a return value of 10?

A developer implements a function that adds a few values.

Function sum(num) {

If (num == undefined) {

Num =0;

}

Return function( num2, num3){

If (num3 === undefined) {

Num3 =0 ;

}

Return num + num2 + num3;

}

}

Which three options can the developer invoke for this function to get a return value of 10? Choose 3 answers
A . Sum () (20)
B . Sum (5, 5) ()
C . sum() (5, 5)
D . sum(5)(5)
E . sum(10) ()