Breeding programs are done to produce varieties of desired characters and those are more productive because there is genetic variation in breeding when two organisms are crossed. Hence, genetic variability is the root of all breeding programs.2. Germplasm is basically the genetic material of cells. If desired alleles are absent in the germplasm, mutations can be induced to express the desirable characters in the varieties.3. Conventional breeding is also known as classical or traditional breeding. It is the development of new varieties using traditional methods. The old breeding methods are still used today to improve the varieties because these methods are not constrained by the availability of a limited number of genes.4. Somaclonal variants and genetically engineered organisms are distinguished and selected by various breeding methods. Somaclonal variants are raised by in vitro culture whereas genetically engineered organisms are produced by manipulating the DNA.Hence, all the statements given in the question are correct.So, the correct answer is '4'.