Add a foreign key to Pet referencing Owner. Also, add a check constraint ensuring PET$\_$AGE is greater than $0.$ Select the correct SQL$.$

a$.$ ALTER TABLE Pet

ADD FOREIGN KEY $($OWNER$\_$ID$)$ REFERENCES Owner $($OWNER$\_$ID$)$

ADD CHECK $($PET$\_$AGE $>0)$;

b$.$ MODIFY TABLE Pet

ADD FOREIGN KEY $($OWNER$\_$ID$)$ REFERENCES Owner $($OWNER$\_$ID$)$

ADD CHECK $($PET$\_$ID $>0)$;

c$.$ ALTER TABLE Pet

ADD FOREIGN KEY $($OWNER$\_$ID$)$ ADD CHECK $($PET$\_$ID $>0)$;