CREATE TABLE Staff $($staffNo VARCHAR $(5)$ PRIMARY KEY, lName VARCHAR $(15),$ branchNo VARCHAR $(5),$ salary DECIMAL$(7,2))$;

INSERT INTO Staff VALUES $(\text{'}$SC$13\text{'},$ 'Smith', $\text{'}$B$003\text{'},17300)$;

INSERT INTO Staff VALUES $(\text{'}$SC$16\text{'},$ 'Brown', $\text{'}$B$003\text{'},8300)$;

INSERT INTO Staff VALUES $(\text{'}$SC$17\text{'},$ 'Doe', $\text{'}$B$005\text{'},20500)$;

INSERT INTO Staff VALUES $(\text{'}$SC$11\text{'},$ 'Jones', $\text{'}$B$005\text{'},15500)$;

SELECT staffNo, lName, branchNo, salary

FROM Staff

WHERE salary $>10000$

GROUP BY branchNo

ORDER BY branchNo, salary;

Given the SQL code above, which piece of data below will be treated as a primary key?