If the interviewer asks about this question, then they are expecting that what is the structure of your application and how you have developed it as per the real time is concerns.
If you want to explain about the n-tier architecture, then you should explain that how you have used it and what all the layers were there in your application.
In a typical n-tier architecture, we mainly make the 4 layers or more as below:
1. UI Layer(this is your application UI part and main application). This could be your windows app, web app, console app, mobile app etc
2. Business object Layer- This could be your library project and contains all the business objects of your application.
3. Business Access Layer- Another library project which cna be used for the business logic layer. The data will be passed through this layer from your UI
4. Data Access layer- Another Library project which contains the data access part. All the communication from the database happens here.The BAL calls this to get the database related stuff.
Apart from this, there could be other layers like Utilities, Connection, Message which can be the supporting classes of the project depending on how you want to make the separation between the layers.
Hope it will be helpful to you.
Pawan Awasthi(DNS MVM)
+91 8123489140 (whatsApp), +60 14365 1476(Malaysia)