Reactants A and reactant B undergo a chemical reaction to form product C.

there is no stairs in bungalow

explanation:

poof

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).

not always but somethings can be reproduced in a laboratory.