You will be given a definition of a task first, then some input of the task.
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: Americans with Sub-Saharan African ancestry for historical reasons: slavery, partus sequitur ventrem, one-eighth law, the one-drop rule of 20th-century legislation, have frequently been classified as black (historically) or African American, even if they have significant European American or Native American ancestry. As slavery became a racial caste, those who were enslaved and others of any African ancestry were classified by what is termed "hypodescent" according to the lower status ethnic group. Many of majority European ancestry and appearance "married white" and assimilated into white society for its social and economic advantages, such as generations of families identified as Melungeons, now generally classified as white but demonstrated genetically to be of European and sub-Saharan African ancestry.
Output:
Who has frequently been classified as Hispanic?