Final answer:
The correct order of the numbers -5.6, 2.2, 9, 12 from least to greatest is A) -5.6, 2.2, 9, 12.
Step-by-step explanation:
To arrange the numbers -5.6, 2.2, 9, 12 in order from least to greatest, we first identify the smallest and largest values. Negative numbers are smaller than positive numbers, so -5.6 would be the smallest. Then we compare the positive numbers in ascending order. Considering this, the correct order of the numbers is -5.6, 2.2, 9, 12.
Hence, the correct option that lists these numbers from least to greatest is:
Options B), C), and D) do not list the numbers in the correct ascending order.