Consider the number 1.23456.
When we multiply it by 10, it becomes 12.3456. The decimal point has moved one place to the right.
If we multiply this number by 10, it becomes 123.456, and we see the decimal point has been moved 2 places to the right relative to where it was in the original number.
To get from 1.23456 to 123.456, we have multiplied by 10×10 = 10².
The exponent 2 in 10² tells how many times 10 is a factor in the product 10×10. It also corresponds to the number of decimal places the decimal point moves to the right when we multiply by 10².
If we were to continue, we would find
... 1.23456 × 10³ = 1234.56
... 1.23456 × 10⁴ = 12345.6
... 1.23456 × 10⁵ = 123456. here, the decimal point has moved 5 places to the right.
The appropriate choice is ...
... C) The decimal point moves 5 places to the right.