By inspection -

Answer D is not possible 16 dimes is >1 dollar,

Answer C is not possible 12 dimes is $1.20

Answer A is inaccurate - 4 dimes is 40 cents and 2 nickels makes 50 cent, in total

The only answer left is B - So, 8 dimes is 80 cents and 4 nickels is 20 cents which is one dollar

So answer B is the correct answer by inspection and verified by adding 8 dimes and 4 nickels

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