In ERD notation, what term specifies the minimum number of entity instances that must participate in a relationship?

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Solve this multiple-choice question and choose the correct option.

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Introduction / Context:Cardinality constraints include both an upper bound and a lower bound. The lower bound indicates whether participation is optional (0) or mandatory (1 or more). Correctly capturing this avoids orphaned or incomplete data. Given Data / Assumptions: We want the minimum number of related instances required. ER models reflect this as optionality or mandatory participation. Common notations: 0..1, 1..1, 0.., 1... Concept / Approach:Minimum cardinality is the lower bound of a relationship. A value of 0 means optional involvement; 1 means mandatory. This propagates to referential constraints and application validations in implementation. Step-by-Step Solution: Identify lower versus upper bound → minimum cardinality is lower bound.Map to optional/mandatory rules for business logic and database constraints.Ensure DDL and application enforce the intended minimum cardinalities. Verification / Alternative check:ER references consistently define lower bound as minimum cardinality. Why Other Options Are Wrong:Maximum cardinality: Upper bound, not lower. ERD / GEC / Participation degree: Not the specific term for the minimum bound in standard ER vocabulary. Common Pitfalls:Failing to align optionality in ERD with NOT NULL and foreign key constraints at implementation time. Final Answer:Minimum cardinality

In ERD notation, what term specifies the minimum number of entity instances that must participate in a relationship?

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