The attribute composed of a single component with an independent existence is called: A. single-valued attribute. B. derived attribute. C. composite attribute. D. atomic attribute.

The attribute composed of a single component with an independent existence is called: A. single-valued attribute. B. derived attribute. C. composite attribute. D. atomic attribute.

To answer this question, we need to understand the definitions of each option and determine which one fits the given description.

A. Single-valued attribute: This refers to an attribute that can have only one value at a time. It does not necessarily imply that the attribute is composed of a single component with an independent existence.

B. Derived attribute: This refers to an attribute that is derived or calculated from other attributes in the database. It does not necessarily imply that the attribute is composed of a single component with an independent existence.

C. Composite attribute: This refers to an attribute that is composed of multiple components or sub-attributes. It does not fit the description of being composed of a single component with an independent existence.

D. Atomic attribute: This refers to an attribute that cannot be further divided into smaller components. It implies that the attribute is composed of a single component with an independent existence.

Based on the given description, the correct answer is D. atomic attribute.