Match List I with List II

List I	List II
A. A developmental design that is a combination of the cross-sectional and longitudinal designs	I. Sequential design
B. A single-case design in which the independent variable is introduced and removed one or more times	II. Factorial design
C. A design with more than one independent variable	III. Reversal design
D. An experimental design in which the participants in the experimental and control groups are related in some way	IV. Connected group design

Correct option is B

(A) A developmental design that is a combination of cross-sectional and longitudinal designs → Sequential design (I) – Correct
A sequential design combines aspects of cross-sectional (studying different age groups at one time) and longitudinal (studying the same individuals over time) designs.
This method helps researchers overcome limitations of both approaches by studying cohort effects and developmental trends simultaneously.

(B) A single-case design in which the independent variable is introduced and removed one or more times → Reversal design (III) – Correct
A reversal design (ABA or ABAB design) is commonly used in single-subject experiments, where the independent variable is introduced, removed, and reintroduced to see its effects on behavior.
Example: Studying the impact of a reinforcement strategy on student performance by applying and removing it.

(C) A design with more than one independent variable → Factorial design (II) – Correct
A factorial design involves multiple independent variables (factors) being tested simultaneously to see their combined effects.
Example: Examining the effects of sleep deprivation (Factor 1) and caffeine intake (Factor 2) on memory performance.

(D) An experimental design in which participants in the experimental and control groups are related in some way → Connected group design (IV) – Correct
A connected group design (also called matched-group or within-subjects design) ensures that participants in the experimental and control conditions are related, such as being matched pairs or the same individuals tested at different times.
Example: Pre-test/post-test studies or twin studies.

Thus, the correct matching is A - I, B - III, C - II, D - IV, making option 2 the correct answer.

Information Booster:
I. Sequential Design
Combines Cross-Sectional and Longitudinal Approaches: Allows researchers to study multiple cohorts over time, providing both immediate and long-term data.
Efficient: Reduces the time needed to observe developmental or long-term changes compared to pure longitudinal designs.
Controls for Cohort Effects: Helps distinguish age-related changes from generational or cohort-specific influences.
Flexibility: Can adapt to new research questions or trends as the study progresses.

II. Reversal Design (ABA Design)
Strong Causal Inference: By reversing conditions (e.g., introducing and withdrawing a treatment), researchers can establish a clear cause-and-effect relationship.
Individual Focus: Ideal for studying individual behavior changes, often used in clinical or behavioral research.
Cost-Effective: Requires fewer participants compared to group-based designs.
Demonstrates Treatment Effectiveness: Clearly shows whether a treatment is responsible for observed changes by comparing baseline (A) and treatment (B) phases.

III. Factorial Design
Examines Multiple Variables Simultaneously: Allows researchers to study the effects of two or more independent variables and their interactions.
Efficient Use of Resources: Provides more information from a single experiment, reducing the need for multiple studies.
Identifies Interaction Effects: Reveals how variables influence each other, offering deeper insights into complex relationships.
High External Validity: Mimics real-world scenarios where multiple factors often interact.

IV. Connected Group Design (Repeated Measures Design)
Reduces Participant Variability: The same participants are used across conditions, minimizing individual differences as a confounding variable.
Increased Statistical Power: Requires fewer participants since each participant serves as their own control.
Efficient: Saves time and resources by reusing the same group for multiple conditions.
Sensitive to Small Effects: Better at detecting subtle changes or effects due to reduced variability.