¿como se llama a las sustancias que sirven para identificar un ácido de una base?​

its temperature is increasing. this causes molecular vibrations to increase.

colors do exist. the color of the sky is actually violet; humans percieve the color of the sky as blue.

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).