A company is planning to use the Azure Cosmos DB service. Do you need to define a predefined schema for the tables on Cosmos DB?

Answer options:

A.Yes
B.No

Answer – B 
Cosmos DB is based on a schema-less design. 
The Microsoft documentation mentions the following. 

For more information on Azure Cosmos DB, please visit the below URL- 

https://docs.microsoft.com/en-us/azure/cosmos-db/introduction