When creating a Search workflow action, which field is required?

Reference:

https://docs.splunk.com/Documentation/Splunk/8.0.3/Knowledge/Setupasearchworkflowaction

A workflow action is a link that appears when you click an event field value in your search results2. A

workflow action can open a web page or run another search based on the field value2. There are two

types of workflow actions: GET and POST2. A GET workflow action appends the field value to the end

of a URI and opens it in a web browser2. A POST workflow action sends the field value as part of an

HTTP request to a web server2. When creating a Search workflow action, which is a type of GET

workflow action that runs another search based on the field value, the only required field is the

search string2. The search string defines the search that will be run when the workflow action is

clicked2. Therefore, option A is correct, while options B, C and D are incorrect because they are not

required fields for creating a Search workflow action.