A Tuple is: a. An attribute in a table that is also a primary key in another table; used to link the two tables. O b. A row in a table that contains data about a specific item in a database table. C. DBMS language that simplifies report creation O d. A database built using the relational data model. The contains information about the structure of the database. O a. data dictionary O b. data warehouse O c. data definition language d. database management system