Answer
See explanation
Work Step by Step
In passing parameters by address we do not provide the variable directly to the function instead we give the address of the variable to the function which can be used to access the variable. For example in following function the variable is passed by address and to print the variable stored at that address we have used the & operator also any changes made by using the & operator will also change the original variable but changes without & operator will have no effect so the final value of original variable will become 1:
fun(Y):
$\space \space \space \space$print(&Y)
$\space \space \space \space$&Y=1
$\space \space \space \space$Y=3
When the parameters are passed by value a copy of them is created and that is used in the local scope of the function and the value of original variable remains unchanged. For example in the following function Y is passed by reference and a copy of original variable is created and no changes were reflected in original variable.
fun(Y):
$\space \space \space \space$Y=10
$\space \space \space \space$print(Y)
