Filter Lookup values in CRM 2011 and CRM 2013 without Javascript

In this Example I filter cities of a country. Follow following steps:

•  Every country have many cities, so i create a 1:N relationship of cities with country entity i.e. in city entity i have lookup of country entity. 
• Now in Account entity i create two lookups one of Country entity and second city entity.

• In city entity I added some sample records of cities and also select their country so that city will be filtered related to that country.                                                                                     

• Now open lookup of city and edit filter record settings as shown in below image. 

• Filtered records are shown below that When I select country Pakistan only cities related to Pakistan are shown and when I select country Afghanistan only cities related to Afghanistan are shown.                                                                                                                                  

Retrieve Record using Odata query filter with GUID of Record

var GroupId = Xrm.Page.data.entity.getId();

var _query = "?$filter=new_GroupId/Id eq (Guid'"+ GroupId +"')";

var obj = RecRetrieveMultiple(_query, 'new_student');