Final answer:
The number 0.008 is correctly expressed in word form as 'eight thousandths' because the digit 8 is in the thousandths decimal place.
Step-by-step explanation:
The number 0.008 in word form is eight thousandths. This is because the number 8 is in the thousandths place, which is three places to the right of the decimal point. Therefore, the correct answer is 'c) Eight thousandths'.