Given the basic ER and relational models, which of the following

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Given the basic ER and relational models, which of the following is incorrect?

1. An attribute of an entity can have more than one value
2. An attribute of an entity can be composite
3. In a row of a relational table. an attribute can have more than one value
4. In a row of a relational table. an attribute can have exactly one value or a null value

Correct Option: C

An attribute of an entity can have more than one value or multivalue.
For example,

Hence, option (a) is correct. Attributes can be composite also, Hence, option (b) is also correct. In the relational table, any attribute can contain only one value which can be null. Hence, option (d) is also correct but by the definition of 1 NF, any attribute in the relational table can contain only one value not more than one values. Hence option (c) is false or incorrect.