Northern Trail Outfitters uses Knowledge Articles to address customer questions in their Napili Community. They need to know if these Articles are helpful to customers when they search for help in the Community.
What is the most efficient way for a Salesforce Admin to get this information from customers?

a. Build a custom Community page that shows the Knowledge Article and have custom fields to capture customer comments.
b. Create a customer survey using custom Lightning components and add it to the home page.
c. Redirect customers to a survey form in an external website that captures their comments on the Knowledge Article.
d. Enable the article voting property on the Article Content component in the article detail page in the Community Builder.