Which among the following types of variables cannot be rank ordered?

Nominal variables only name or label categories and carry no inherent order, so they cannot be rank ordered.

Gender or religion are nominal, where one category is not higher or lower than another.

Ordinal variables can be rank ordered, since their categories follow a meaningful sequence like ranks or grades.

Interval variables are ordered and have equal spacing between values, such as temperature in Celsius.

Ratio variables are ordered, equally spaced and have a true zero, such as weight or height.

Only nominal data among the four permit merely counting frequencies, not ordering.