Q: 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: There are technical limitations to archiving a web site, and as a consequence, it is possible for opposing parties in litigation to misuse the results provided by web site archives. This problem can be exacerbated by the practice of submitting screen shots of web pages in complaints, answers, or expert witness reports, when the underlying links are not exposed and therefore, can contain errors. For example, archives such as the Wayback Machine do not fill out forms and therefore, do not include the contents of non-RESTful e-commerce databases in their archives.
A:
What kind of limitations exist in keeping copies of the Wayback Machine?