For the following SQL Database questions choose the correct response:

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Question a. : A key in a relational database table i. is a minimal set of attributes. ii. uniquely identifies a tuple in the table. iii. both i. and ii are correct iv. neither option i. nor option ii

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Question b. :A candidate key in a relational database table

i. is a minimal set of attributes. ii. uniquely identifies a tuple in the table. iii. both i. and ii are correct iv. neither option i. nor option ii.

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Question c. : A primary key defined in SQL create table statement

i. is a minimal set of attributes ii. uniquely identifies a tuple in the table. iii. is selected from a set of candidate keys. iv. All of the above are correct.

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Question d. :In relational model, a relation contains

i.a set of records ii.a set of unique records. iii. either i. or ii iv. neither i. nor ii.