What will the majority of pathogens in food be killed by?
a) antimicrobial secretions from the sebaceous glands in the skin

b) mucus in the trachea

c) acid in the stomach

d) nose hairs

if im correct it is acid in the stomach

Explanation:

Freezing reduces the number of Campylobacter bacteria on raw meat but will not kill them completely, so proper heating of foods is important. Campylobacteriosis occurs more frequently in the summer and is most common in infants and young children.

the last one: artificial selection/genetic engineering

plant breeding is modifying the genetic composition of the plant - but this isn't cloning (which is specifically introducing a gene into a genome). but you are artificially selecting for the phenotype that you want.

the second one is literally genetic engineering - the gene would have been cloned first and then inserted or genetically engineered into the new plant cell (the cotton).