Update README.md

README.md

@@ -66,7 +66,7 @@ This dataset contains two main subsets designed for multimodal retrieval challen
 - `pos_item_contents`: Sequence of positive item contents (empty, removed for private test set)
 
 **Task Types**:
-1. **Image-to-Document Retrieval**: When `question` is empty
+1. **Image-to-Document Retrieval**: When `question` is empty (image query)
 2. **Multimodal Retrieval**: When `question` contains text (image + text query)
 
 ### challenge_passage (47,300 rows)
@@ -77,6 +77,7 @@ This dataset contains two main subsets designed for multimodal retrieval challen
   - Structured details about persons (birth/death dates, occupations, locations, etc.)
 - `page_screenshot`: Associated image filename (string)
 
+For the retrieval task, you will need to retrieve the corresponding passage from the 47K-passage pool for each sample in challenge_data.
 
 ## Images