What is 9.43056 rounded to three decimal places?

To round the number 9.43056 to three decimal places, the focus is on the fourth decimal place to determine whether to round up or keep the third decimal place as is. The number in the third decimal place is '0' and the number in the fourth decimal place is '5'.

According to rounding rules, if the digit in the next decimal spot (fourth decimal) is 5 or greater, you add one to the digit being rounded (third decimal). Since 5 is indeed equal to 5, we increase the '0' in the third decimal place by one. This results in changing 9.430 to 9.431.

Thus, rounding 9.43056 to three decimal places correctly gives 9.431. This makes it clear why this specific choice is the correct answer.