given variant for the abstract syntax of this language.

type bop larr

I Add

Sub

I Mul

$|$

$$Div

type expr larr

Num of number

$|$

$$Var of string

$|$

$$FuncExpr of string

$\backslash$times

$$expr

$|$

$$CallExpr of expr

$\backslash$times

$$expr

$|$

$$BopExpr of expr

$\backslash$times

$$bop

$\backslash$times

$$expr why is the following the correct answer for c please explain.$($c$)$ Formally define the big step semantics of this language.

$\frac{\text{v}\text{i}\text{n}\text{Z}}{vv}M$

$\frac{?}{E|--xE(x)}$ VAR

$\frac{?}{E+x*t(x*t,E)}$FuNC

$\frac{E_1|--t_1(x*t_3,E_2),E_1|--t_2{v}_1,E_2[x|v_1]|--t_3{v}_2}{E_1|--t_1{t}_2{v}_2}$ CALL

$\frac{E|--t_1{v}_1,E|---t_1{v}_2}{E|--t_1+t_2{v}_1+v_2}$ADD

$\frac{E|--t_1{v}_1,E|---t_1{v}_2}{E|--t_1-t_2{v}_1-v_2}$SUB

$\frac{E|---t_1{v}_1,E|---t_1{v}_2}{E|--t_1**t_2{v}_1**v_2}\frac{?}{MU}L$

$\frac{E|--t_1{v}_1,E|---t_1{v}_2}{E|---\frac{t_1}{t_2}\frac{v_1}{v_2}}$ DIV