In lentils, the c gene has two different alleles. cscs homozygotes have spotted seeds, cdcd homozygotes have dotted seeds, and cscd heterozygotes have seeds with both spots and dots. this indicates that

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).

answer; microsoft;