Which of the following is less than 10.6?

First, compare the integer part of each choice.

10 < 11 < 18, so we cross out choice B and D.

Second, convert the mixed numbers to decimals.

10 58/125= 10 464/1000=10.464 < 10.6

10 18/25 = 10 72/100 =10.72 > 10. 6

Therefore, the choice A is correct.