You have a LUIS application. You plan to define entities to provide hints to another entity or intent. Given the requirement that you need to create an entity for credit cards, which entity type would you use amongst the following choices? (select one answer choice)

Answer options:

A.List entity
B.Regex entity
C.Prebuilt entity
D.ML entity

Correct Answer: B
Option A is incorrect because a list entity represents a fixed and closed set of related words along with their symptoms. They are case sensitive and require an exact match.
Option B is correct because Regex entity type extracts entities based on the regular expressions. They are not case sensitive. They are best suited for credit cards as you can have predefined alphanumeric values in a certain format for the credit cards.
Option C is incorrect because prebuilt entities are commonly used for data like name, date and currency.
Option D is incorrect because ML based entity types use a context to extract entities. As the name suggests they are machine learning based entities and rely on example labels to identify the data.
Reference:
To learn more about Entity types in LUIS application, use the link given below: 

https://docs.microsoft.com/en-us/azure/cognitive-services/luis/luis-concept-entity-types