You create a chatbot for the online shop. The shop is selling specialized products for manufacturing machinery. 
Chatbot`s users should have an option to make inquiries about a particular piece of equipment by selecting a machine type from the option list. 
What should you add to the bot to provide an efficient service to your customers?

Answer options:

A.Power Automate flow
B.Custom entities
C.Conditions
D.New trigger phrases
E.Questions

Correct Answer: B 
Power Virtual Agents service provides a set of pre-built entities that reflects the most common information like age, color, places, money, language, etc. These entities also include standard business terminology. 
However, some business organizations need to create the "vocabulary" of their specialized language. It helps bots to understand the customers` questions or requests about specific business domains. 
For such cases, the Power Virtual Agents service provides functionality to create your business-specific entities and teach a chatbot to recognize these entities in conversation, answer questions, and take appropriate actions. 
If you need to create a custom entity, you can select the “Entities” in the main menu and push the “+ New custom entity” button on the top bar. Portal opens a new screen. You need to provide the entity name and the list of items with their synonyms. 

When you create a conversation path for your bot, you can provide possible questions and link custom entities to the bot’s answer. 

All other options are incorrect. 
For more information about Power Virtual Agents custom entities, please visit the below URLs: 

https://docs.microsoft.com/en-us/learn/modules/manage-power-virtual-agents-topics/4-entities
https://docs.microsoft.com/en-us/power-virtual-agents/advanced-entities-slot-filling