In cryptography, a Caesar cipher is one of the simplest and most commonly known cryptographic techniques. The Caesar cipher encodes text by replacing each letter with another from a fixed number of positions left or right along a cyclic alphabetic sequence. The English alphabet contains 26 characters and the first letter in the alphabet is assigned index position 0. For example, a Caesar cipher with a left shift of 7 applied to English text will encode the letters H and D to A and W respectively.
Given a letter with an English alphabetic position called POSITION, select the option below which would correctly determine its new index according to a Caesar cipher with a left shift of 9.
( POSITION - 9 ) mod 26
( POSITION + 26 - 9 ) div 26
( POSITION + 26 - 9 ) mod 26
( POSITION - 9 ) div 26
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