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.

Passage: The time and space hierarchy theorems form the basis for most separation results of complexity classes. For instance, the time hierarchy theorem tells us that P is strictly contained in EXPTIME, and the space hierarchy theorem tells us that L is strictly contained in PSPACE.
What does not form the basis for most separation results of complexity classes?

Passage: In the late 19th century with the discovery of the electron, and in the early 20th century, with the discovery of the atomic nucleus, and the birth of particle physics, matter was seen as made up of electrons, protons and neutrons interacting to form atoms. Today, we know that even protons and neutrons are not indivisible, they can be divided into quarks, while electrons are part of a particle family called leptons. Both quarks and leptons are elementary particles, and are currently seen as being the fundamental constituents of matter.
What field of physics began in the 19th century?

Passage: From the Rigveda until the time of Pāṇini (fourth century BCE) the development of the early Vedic language can be observed in other Vedic texts: the Samaveda, Yajurveda, Atharvaveda, Brahmanas, and Upanishads. During this time, the prestige of the language, its use for sacred purposes, and the importance attached to its correct enunciation all served as powerful conservative forces resisting the normal processes of linguistic change. However, there is a clear, five-level linguistic development of Vedic from the Rigveda to the language of the Upanishads and the earliest sutras such as the Baudhayana sutras.

When was the Samaveda witten?