You are an IT-administrator in a company that is planning to migrate workloads to Azure and Office 365. You have investigated the different authentication methods available when deploying Azure AD Connect and decided that password hash sync and password write-back is the best solution for your organization. 
What type of license is required to achieve this? You must choose the most cost effective solution.

Answer options:

A.Azure AD Free
B.Azure AD P1
C.Azure AD P2
D.Enterprise Agreement

Correct Answer: B 
The license requirement for enabling Azure AD self-service password reset writeback is Azure AD P1.
Option A is incorrect. You need to upgrade to an Azure AD paid tier.
Option C is incorrect. Azure AD P2 will enable you to configure the desired solution, but this license is more expensive than Azure AD P1.
Option D is incorrect. This license type is associated with Azure subscription.
Reference: 
To know more about password writeback license requirements, please refer to the link below: 

https://docs.microsoft.com/en-us/azure/active-directory/authentication/tutorial-enable-sspr-writeback