Select all statements below which are true

A Rations and proportions compare items with the same labels.
B Rations and proportions compare items with different labels
C Ratios express the relationship between two or more items
D Ratios express the relationship between only one item.

C Ratios express the relationship between two or more items.

To determine which statements are true, let's examine each of them:

A) Rations and proportions compare items with the same labels.
B) Rations and proportions compare items with different labels.
C) Ratios express the relationship between two or more items.
D) Ratios express the relationship between only one item.

To begin with, we should clarify that both statement A and B contain a typographical error. The correct term is "ratios" instead of "rations." Now, let's evaluate each statement:

A) "Ratios and proportions compare items with the same labels."
This statement is incorrect. Ratios and proportions can compare items with the same labels or with different labels. The labels are irrelevant; what matters is the relationship between the quantities being compared.

B) "Ratios and proportions compare items with different labels."
This statement is correct. Ratios and proportions can indeed compare items with different labels. For example, we can compare the ratio of height to weight, which are two different measurements.

C) "Ratios express the relationship between two or more items."
This statement is correct. Ratios do express the relationship between two or more items. A ratio describes how quantities in a group relate to each other. For instance, a ratio of 2:3 indicates that there are two of one item for every three of another.

D) "Ratios express the relationship between only one item."
This statement is incorrect. Ratios express the relationship between two or more items. Comparing the quantities of one item alone does not involve a ratio.

Based on our analysis, the correct statements are B and C.

C Ratios express the relationship between two or more items.