How to make Inline form to select a particular node type of chosen category

I have a complex case scenario and I need urgent help.
On new account/registration page, along with other details user is asked to select a particular taxonomy term (hierarchical select) like: mobile>mobile phones / mobile accessories atc. or real estate > flats for sale/ appartments on rent/paying guest etc. I have separate Content types for each of these taxonomy terms with a particular taxonomy term set as default category. LIke Mobile phone content type has mobile phone term set as default category.
I want to lead users on new account registration to add a particular content type selected automatically on the basis of his chosen category in registration form.
How to do it.
I have created Item Category with term and hierarchical select widget. User select the item category on registration page.
Now task is to present Add Particular content type form on the basis of his chosen category.
For this I created another Ref. Category with field type Entity reference and Inline entity form as widget. Now on filed edit page I selected Target as Node and then selected all the node types, out of which one particular type needs to be presented before user.

Now on new account registration page, Inline entity form is furnishing an Ad Content form .. but it is doing it randomly. That is expected as I have not yet told it to select a particular content type only. I tried for hours, but unfortunately I could not figure out how to do it. How can I direct Inline Entity Form to select a particular node type on the basis of chosen term category by the user?
I will be very grateful for any help in this. Please help.