Consider Relational DataBase $($RDB$)$ operations. Which of the following

describes a Union operation?

Extracts tuples $($rows$)$ from a relation.

Extracts fields $($columns$)$ from a relation and eliminates duplicates.

Forms a new relation from $2$ relations according to a condition between two shared

attributes.

Forms a new relation from $2$ relations by including all the tuples in both relations

without condition. All three relations have the same schema.