The correct answer is B.
There's no statically significant association between the exposure and the disease. The risk ratio does not follow the normal distribution, even it does not depend on sample size in comparison groups. The natural rr is approximately normally distributed and is used to produce confidence interval which is for the relative risk.
Out of the options I would have to say Penetrating Keratoplasty, I am not sure
Refined grain products like bread, flour tortillas, white rice, cornmeal, crackers etc are enriched with riboflavin, niacin, iron and thiamin.
Enriched grains is finely ground endosperm of the kernel. Enriched grain products are good as a source of iron and four types of vitamin B which includes niacin, thiamin, folic acid and riboflavin and also contains some complex carbohydrates.
Wheat and rice are a staple diet in many regions of the world but excessive polishing and refining the cereals removes the essential nutrients or vitamins which have their own important physiological roles.
The answer is mitochondria
