This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

[EX Q]: Passage: Other types of lossy compressors, such as the linear predictive coding (LPC) used with speech, are source-based coders. These coders use a model of the sound's generator (such as the human vocal tract with LPC) to whiten the audio signal (i.e., flatten its spectrum) before quantization. LPC may be thought of as a basic perceptual coding technique: reconstruction of an audio signal using a linear predictor shapes the coder's quantization noise into the spectrum of the target signal, partially masking it.
[EX A]: What is thought of as a basic signal coding technique?

[EX Q]: Passage: Present-day Christian religious bodies known for conducting their worship services without musical accompaniment include some Presbyterian churches devoted to the regulative principle of worship, Old Regular Baptists, Primitive Baptists, Plymouth Brethren, Churches of Christ, the Old German Baptist Brethren, Doukhobors the Byzantine Rite and the Amish, Old Order Mennonites and Conservative Mennonites. Certain high church services and other musical events in liturgical churches (such as the Roman Catholic Mass and the Lutheran Divine Service) may be a cappella, a practice remaining from apostolic times. Many Mennonites also conduct some or all of their services without instruments. Sacred Harp, a type of folk music, is an a cappella style of religious singing with shape notes, usually sung at singing conventions.
[EX A]: What are some present day Christian churces nolonger use the a capella form?

[EX Q]: Passage: Cork was one of the most rail-oriented cities in Ireland, featuring eight stations at various times. The main route, still much the same today, is from Dublin Heuston. Originally terminating on the city's outskirts at Blackpool, the route now reaches the city centre terminus of Kent Station via Glanmire tunnel. Now a through station, the line through Kent connects the towns of Cobh and Midleton east of the city. This also connected to the seaside town of Youghal, until the 1980s.[citation needed]
[EX A]:
What is one or the most rail oriented cities in Europe?