Step 1: Understanding the Allocative Function
The allocative function of financial markets ensures that scarce financial resources are directed towards the most productive economic activities.
Step 2: Evaluating the Statements
- The assertion states that well-performed allocation directs resources to highly productive firms, which is true.
- The reason explains that the allocative function guides funds to the best investment opportunities, making it a valid explanation.
Since the reason accurately supports the assertion, option (A) is correct.
Conclusion: The correct answer is (mathbf{(A)}), as the explanation correctly justifies the assertion.