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In an ER design for a listed company's compliance system, 'Dependent' (family members of an employee) has no key of its own and is identified only through the Employee it belongs to, using the employee ID plus the dependent's name. Which statement correctly describes this design?

Dependent is a weak entity. It has no key of its own, so it is identified through its owner Employee. Its primary key combines the employee ID with the partial key, the dependent's name, and it is drawn as a double rectangle.

  1. ADependent is a weak entity with a partial key, and its primary key combines the owner's key with that partial keyCorrect
  2. BDependent is a strong entity, because it has a composite attribute in its key
  3. CDependent is an associative entity that must hold no attributes of its own
  4. DDependent is a derived attribute of Employee stored as a multivalued oval

Explanation

A weak entity lacks a full key and depends on an identifying owner entity. Its name acts as a partial (discriminator) key, and the table's primary key is the owner's key plus the partial key. It is shown with a double rectangle. The other options misdescribe the construct.

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