Critical Reasoning

Pasteurization of milk is a process by which milk is heated to a certain temperature and then rapidly cooled, killing pathogens and increasing the milk's shelf life. Recently pasteurization has come under fire because it has been found that during pasteurization many helpful digestive enzymes are destroyed, and many dangerous pathogens, including the MAP bacterial strain, which is linked to Crohn's disease, are not. Because of this, some people have started drinking 'raw milk' milk, which is not pasteurized or otherwise processed. Proponents of pasteurization point out that that pasteurization is still necessary to reduce bacterial contamination, and that heating milk at home also kills beneficial digestive enzymes. Raw milk drinkers argue that this argument is beside the point, since most people who drink milk do not heat it first, or else misleading, since ___________________.

A.many of the proponents of pasteurization are dairy farmers who rely on the increased shelf life of pasteurized milk to ship their product farther away.
[spoiler]This argument may explain the motivation of milk pasteurizers, but doesn't explain why their claim is misleading. [/spoiler]
B.it is clear that killing pathogens that may be present in milk is not the only effect of pasteurization.
This is already mentioned in the passage, and is not in dispute.
C.cooked milk is generally heated to a higher temperature than pasteurized milk is.
[spoiler]If anything, this would strengthen the pasteurizers' point.[/spoiler]
D.milk that is subjected to both processes loses even more of the helpful digestive enzymes than milk subjected to either process alone.
This is the credited response.
E.pasteurization serves to ensure a longer shelf life for milk, while heating milk is usually the final step in its preparation.
This is outside the scope of the passage. When each step occurs in the process has no impact on what happens to the milk is usually the final step in its preparation.

Choice (D) is the correct one. Which states that the total amount of killed beneficial digestive enzymes is the sum of amount of enzymes that were killed by heating mill and pasteurization.