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

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:

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