Select the odd group of numbers. (NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into its constituent digits. E.g.13 - Operations on 13 such as adding /subtracting /multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed)

(171 - 169 - 167)

The logic followed here is :

(153 - 151 - 147) = 153 - 2 = 151 , 151 - 4 = 147

(171 - 169 - 167) = 171 - 2= 169 , 169 - 2 = 167 odd

(183 - 181 - 178) = 183 - 2 = 181 , 181 - 3 = 178

(201 - 198 - 197) = 201 - 3 = 198 , 198 - 1 = 197