Definition: 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.

Positive Example 1 -
Input: Context : Isaac Nicola Romero (1916 in Havana, Cuba -- 1997) was a prominent Cuban guitarist and one of the founders of the modern Cuban Guitar School. 
Subject : Isaac Nicola 
Relation : place of birth
Output: What was Isaac Nicola's city of birth?

Positive Example 2 -
Input: Context : Both Timur and Demir are popular male names in Turkey today. 
Subject : Timur 
Relation : noble title
Output: What was the title that Timur held?

Negative Example 1 -
Input: Context : The Boeing 601 (sometimes referred to as the BSS-601, and previously as the HS-601) is a communications satellite bus introduced in 1987 by Hughes Space and Communications Company. 
Subject : Boeing 601 
Relation : service entry
Output: What is Boeing 601?

Negative Example 2 -
Input: Context : In 1956 and 1957, the British and Commonwealth system of battle honours recognised participation in the Battle of Villers-Bocage by the award to 11 units of the battle honour Villers Bocage, for service in expanding the bridgehead from 8--15 June. 
Subject : Battle of Villers-Bocage 
Relation : point in time
Output: who recognised participation in the Battle of Villers-Bocage?

Now complete the following example -
Input: Context : For decades only Episode 3 of The Enemy of the World was known to have survived erasure, but the five missing episodes were announced as recovered by the BBC on 11 October 2013 along with four of the missing episodes of the following serial, The Web of Fear. 
Subject : The Enemy of the World 
Relation : series
Output: 


Output: To which series does The Enemy of the World belong?