You create an instant flow that retrieves the SharePoint items. Sometimes, you are getting the HTTP 404 error — "Item Not found." This error stops the flow execution. You think that the error can come from the "Get item" action when the flow retrieves the non-existing items. You need to resolve this case without stopping the flow execution. 
Please select three steps you should take to mitigate the 404 error.

Answer options:

A.Add Case for 404 error
B.Add Terminate action with “Succeeded” status
C.Add Switch for outputs(‘Get_item’)
D.Remove the “Get item” action
E.Configure run after options for “Get item”
F.Add new “Get Item” action

Correct Answers: A, C and E 
The HTTP 404 error — "Item not found" is a legitimate case that a programmer needs to capture and resolve. This error and other Web API`s errors, like 500 for unexpected conditions, come from the connectors. In your flows, you need to mitigate such API`s errors without stopping the flow execution. 
After the failed node, you add a Switch action. Then you create the cases for successful execution (HTTP code 200) of the "Get Item" node and for error codes 404 and 500.
Power Automate provides an option "Configure run after" that helps flow to proceed if a node fails. You can see this option in a menu when you click on the three dots in a node. By default, this option is set to "is successful" (Number 1). You need to check "has failed" (Number 2). This setting tells the flow to run the Switch after the "Get item" action even if the "Get Item" fails. 

Then in the Switch node, we need to add a condition. When “Get item” fails, the action outputs (Number 1) body provides the status code and a message (Number 2). 

You provide the code to the Switch as “On” expression: actions(`Get_item`).outputs.body.status 
And then update the Switch cases, including the Case for 404 error. 
After you check your flow with the Flow checker and run the Manual Test, you will get the following results for a Successful run (Number 1). The "Get Item" action failed and produced the 404 code (Number 2). The Switch node captured the 404 code (Number 3) as an Input and directed the flow to Case 2 — "Equals - 404" (Number 4). The flow successfully created the missing Item (Number 5) and sent an email notification (Number 6). 

All other options are incorrect. 
For more information about the troubleshooting of the Web API’s errors, please visit the below URLs: 

http://www.lifeonplanetgroove.com/advanced-error-handling-with-power-automate/#!prettyPhoto
https://docs.microsoft.com/en-us/azure/logic-apps/workflow-definition-language-functions-reference#outputs