Question

for which survey question would assigning numbers to the response categories be meaningful?
a) where do you mainly use this product?
outdoors indoors in the garage in the cellar
b) which of our products do you use most often?
allclean brightpolish evershine realglow
c) how likely are you to recommend our products to others?
very likely likely somewhat unlikely completely unlikely
d) who has recommended our products to you?
my spouse my neighbor my relatives no one

Explanation:

Assigning numbers is meaningful when there is an order or scale. In option C, the responses "Very likely", "Likely", "Somewhat unlikely", "Completely unlikely" form an ordinal - scale. We can assign numbers to represent the degree of likelihood, for example, 4 for "Very likely", 3 for "Likely", 2 for "Somewhat unlikely" and 1 for "Completely unlikely". Options A, B and D are nominal - scale questions where the categories have no inherent order and assigning numbers would be arbitrary.

Answer:

C. How likely are you to recommend our products to others?
Very likely
Likely
Somewhat unlikely
Completely unlikely