As a business analyst, it's important to understand the relationships among requirements.

Linked is not a valid relationship type among requirements. Requirements can have different types of relationships, such as derivation, satisfaction, verification, refinement, traceability, dependency, conflict, or overlap1. These relationships can help to analyze the impact, consistency, completeness, and quality of the requirements2. However, linked is not a specific or meaningful term to describe how requirements are related.

The other options are valid relationship types among requirements:

Necessity is a relationship type that indicates that a requirement is essential for achieving a goal or satisfying a need3.

Cover is a relationship type that indicates that a requirement addresses or fulfills a stakeholder need or expectation4.

Subset is a relationship type that indicates that a requirement is a more detailed or specific version of another requirement5.

References:

Relationship Analysis in Requirements Engineering, section “Relationship Types”

A Guide to the Business Analysis Body of Knowledge® (BABOK® Guide), version 3, chapter 6, section 6.1.4.1

Necessity, section “Description of Change”

Cover, section “Description of Change”

Subset, section “Description of Change”