Hi heyholetsgo,
This is a very interesting question! What is the source?
The contradiction is between the rate of decrees between Fat and calorie 25% consumption and heart diseases 50%.
Option C states that Fat consumption is more important that calorie consumption in preventing heart disease. If that is the case then the rate of heart attacks should be proportional since the calorie consumption was similar to fat consumption as per the argument.
Option D implies that trans fats are the major cause of heart attacks, since they were banned and were not consumed a major cause of heart disease was absent which resulted in the disproportionate drop in heart attacks.
Please let me know what you think of the above explanation.