Which of the following is a formal definition of proximity?
O Nearness and closeness are synonyms of proximity.
Proximity, which is a noun that means closeness in space or time, is worth a lot of points in Scrabble if you can manage to
spell it.
Financial planning changes with your proximity to retirement; as retirement nears, you should shift to low-risk investments.
O The thieves stopped before they got too close to the bank vault, afraid the proximity alarm would go off.

Letter B starts well, indeed defining the word "proximity". However, it suddenly shifts to expressing an opinion about the use of that word when playing a game, which is something a definition should not contain.

Letters C and D are merely examples of sentences containing the word "proximity". They do not define the word at all.

For those reasons, letter A seems to be the best option. One way to define a word is by providing synonyms, that is, other words that have the same meaning as the one being defined.

With the information above in mind, we can choose letter A as the best option.

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