To answer this question, you need to understand the relationship between servlet methods and HTTP methods.
In the Java Servlet API, there are several methods that correspond to different HTTP methods. These methods are used to handle requests from clients and provide appropriate responses. The commonly used methods are:
A. doGet() - This method is used to handle the GET requests. It retrieves information from the server and sends it back to the client.
B. doPost() - This method is used to handle the POST requests. It submits data to the server for processing.
C. doConnect() - This is not a valid servlet method. There is no HTTP method called CONNECT.
D. doOptions() - This method is used to handle the OPTIONS requests. It provides information about the communication options available for the requested resource.
E. doHead() - This method is used to handle the HEAD requests. It retrieves the headers of the response without the response body.
F. doRequest() - This is not a valid servlet method. There is no HTTP method called REQUEST.
Based on the above explanations, the valid servlet methods that match up with HTTP methods are A. doGet(), B. doPost(), D. doOptions(), and F. doRequest().
Therefore, the correct answer is A, B, D, F.