In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank.

A puzzle is a game, challenge, or toy that (1)________ one’s inventiveness or knowledge. The solver of a puzzle is supposed to (2)___________ parts together logically to arrive at the correct or enjoyable solution to the challenge. Crossword puzzles, word-search puzzles, number puzzles, relational puzzles, and logic puzzles are examples of puzzle (3)________. Puzzles are frequently developed for fun purposes, but they may also result from (4)_________ mathematical or logical challenges. In such circumstances, its answer might make an important (5)_________ to mathematical research.