1280
Previously , we showed that lack of retinoids thickens the alveolar basement membrane and increases collagen IV , which are reversed by retinoic acid , the main biologically active vitamin A form .
 Chemical: retinoids; Chemical: retinoic acid; Chemical: vitamin A
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: retinoids, retinoic acid, vitamin A 
Answer:
 Chemical: retinoids; Chemical: retinoic acid; Chemical: vitamin A