Choose the alternative which best expresses the meaning of the highlighted idiom/phrase: "$I$ hope it will not $put\, you\, out$ if $I$ am late."

Some idioms/phrases are given below together with their meanings. Choose the correct meaning of the idiom/phrase: "To smell a rat".

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He $went \,back\, on$ his promise to vote for me.

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You have to be $a\, cool\, customer$ and be patient if you want to get the best buys.

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Despite the trust bestowed on the minister, he turned out to be $a\, snake\, in\, the\, grass$ during the revolution.

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He $passed\, himself\, off$ as a noble man.