Select the relational algebra expression that is equivalent to the following $SQL$ statement.

SELECT name FROM student S$,$ Reault R WHERE

S$.$no $=$

R$.$no AND grade$-\text{'}{A}^{\text{'}}$

a$.$ Student Result $($:$)\}$

b$.$ Student Result $($:$)\}$

c$.\text{'}$ Student $$ Result $($:$)\}$

d$.$

$))=({(}^{\text{'}}A{A}^{\text{'}}(R)$