You have six variables: X, Y, A, B, C and D. The following cause-and-effect statements hold: 1. A affects both X and Y. 2. B is caused by X. 3. X affects Y. 4. Y affects C. 5. B also affects D. 6. D affects Y. Using these statements, draw a DAG (or conceptualize it) and then consider the following claims: 1. A is a confounder of the relationship between X and Y. 2. B is a collider on the path A -> X -> B <- D -> Y. 3. D lies on a direct path from X to Y. 4. Conditioning on A would block at least one backdoor path between X and Y. Which combination of statements above is correct?