You will be given a context, a subject and a relation. Your task is to generate a question based on the subject and relation. The generated question should include the given subject. Try to use a minimum number of words that are not present in either context, subject or relation while generating question.

Context : The Fiat L6/40 was a light tank used by the Italian army from 1940 through World War II. It was designed by Fiat-Ansaldo as an export product, and was adopted by the Italian Army when officials learned of the design and expressed interest. 
Subject : Fiat L6/40 
Relation : service entry
In what year did Fiat L6/40 enter service?

Context : The Hanging Tree is a 1959 Technicolor film directed by Delmer Daves. 
Subject : The Hanging Tree 
Relation : director
The main director of The Hanging Tree was who?

Context : The Tiger II was under-powered, like many other heavy tanks of World War II, and consumed a lot of fuel, which was in short supply for the Germans. 
Subject : Tiger II 
Relation : service entry

In what year did Tiger II enter service?