The structure labeled. “X” represents: a) A tetrad
b) Daughter cells
c) DNA replication

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?

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).

bradycardia ( blood presssure below 120/80mmhg )

it is contraindicated to give nitroglycerin to patients with blood pressure that is lower than normal range because the drug can cause blood pressure to drop further. it can lead to paradoxical bradycardia and less commonly, threatening hypotension.