Answer: weak-form efficient.

## Explanation **Correct Answer: A (weak-form efficient)** **Why this is correct:** 1. **Weak-form market efficiency** states that all past price and volume information is already reflected in current prices. This means that technical analysis (which uses historical price patterns) cannot generate abnormal returns. 2. **Serial correlation testing** examines whether there is any relationship between past returns and future returns. If markets are weak-form efficient, there should be no serial correlation - returns should be random and unpredictable based on past patterns. 3. By testing for serial correlations, the analyst is specifically checking whether past return patterns can predict future returns, which is the core test of weak-form efficiency. **Why other options are incorrect:** - **B (semi-strong-form efficient):** Semi-strong-form efficiency states that all publicly available information is reflected in prices. Testing this would require examining whether public announcements or fundamental information can generate abnormal returns, not just serial correlations in returns. - **C (strong-form efficient):** Strong-form efficiency states that all information (public and private) is reflected in prices. Testing this would require examining whether even insider information can generate abnormal returns, which is beyond what serial correlation testing can assess. **Key Takeaway:** - Weak-form efficiency → tests historical price patterns (serial correlation, technical analysis) - Semi-strong-form efficiency → tests public information (earnings announcements, news) - Strong-form efficiency → tests all information including private/insider information

Author: LeetQuiz .