A loop should output $1$ to n$.$ If n is $5,$ the output is $12345.$ What should XXX$,$ YYY$,$ and ZZZ be$?$

Flowchart has $2$ variables $($integer n$,$ integer i$)$ and $7$ nodes. Node $1$ is the start node and points to node $2.$ Node $2$ code: n $=$ Get next input Node $2$ points to node $3.$ Node $3$ code: XXX Node $3$ points to node $4.$ Node $4$ code: while YYY Node $4$ points to nodes $5($condition is true$)$ and $7($condition is false$).$ Node $5$ code: Put ZZZ to output Node $5$ points to node $6.$ Node $6$ code: i $=$ i $+1$ Node $6$ points to node $4.$ Node $7$ is the end node.

a$.$

XXX: i $=0/$ YYY: i $<$ n $/$ ZZZ: i

b$.$

XXX: i $=0/$ YYY: i $<$ n $/$ ZZZ: i $+1$

c$.$

XXX: i $=1/$ YYY: i $<$ n $/$ ZZZ: i

d$.$

XXX: i $=1/$ YYY: i $<$ n $/$ ZZZ: i $+1$