Considering relational database, functional dependency between two attributes A and B is denoted bySelect one:a.A → Bb.AB → Rc.B ← Ad.R ← ABClear my choice

To address the question about functional dependency in relational databases, let's analyze the options provided:

1. Understanding Functional Dependency: Functional dependency between two attributes $A$ and $B$, denoted as $A \rightarrow B$, means that for a given value of $A$, there is exactly one value of $B$. This is a fundamental concept in database normalization and design.

2. Analyzing the Options:

   • a. $A \rightarrow B$: This is correct, as it denotes that $A$ determines $B$.
   • b. $AB \rightarrow R$: This implies that the combination of $A$ and $B$ determines $R$, which is not a standard representation of the functional dependency between two attributes.
   • c. $B \leftarrow A$: This is a reverse representation and is not standard for defining functional dependency.
   • d. $R \rightarrow AB$: This suggests that $R$ determines both $A$ and $B$, which does not describe the direct dependency of $B$ on $A$.

Conclusion:

The correct representation of functional dependency between two attributes $A$ and $B$ is:

Final Answer: a. $A \rightarrow B$