What is the output of the search expression 'apple NOT W/20 pear'?

The search expression 'apple NOT W/20 pear' is designed to retrieve documents that contain the term "apple" while excluding any instances where "pear" appears within 20 words of "apple." Therefore, the output will be documents with "apple" that do not have "pear" in close proximity.

Selecting the choice stating that it provides different documents than the reverse search reflects an understanding of how proximity and negation operate in search queries. When you reverse the terms in the expression to 'pear NOT W/20 apple,' you are looking for documents that contain "pear" but not "apple" within the same specified range of words. Since the searches are fundamentally targeting different key terms and their contexts, it's logical to conclude that the resulting sets of documents will indeed differ significantly.

In contrast, statements suggesting that the output would consist solely of results containing "apple" or suggesting combined results do not accurately represent the functionality of the search terms involved, especially regarding the function of negation and word proximity. Proximity searches specifically control the arrangement of keywords, which is a critical aspect of understanding how results will differ between this search and its reverse.