In the pedigree method of hybridization up to which generation the plants are tested and released for cultivation
A. $F_2$ Generation
B. $F_3$ Generation
C. $F_4$ Generation
D. $F_6$ Generation

Hint: The cross-breeding between two genetically dissimilar plants is known as hybridization. This is involved in the development of progeny with desirable characters from the parents.

Complete answer:
During pedigree analysis, plants up to several generations can be traced and analyzed for the genotypes, phenotypes as well as several dominant and recessive traits. During the pedigree method of hybridization, the plants up to $F_3$ generation can be tested and released for cultivation.
Considering the other given options:
-$F_2$ generation can be straightaway used for testing and release for cultivation since it is one of the first generations produced after the crossing. Thus it is not the right option.
-The plants produced in the $F_4$ generation cannot be used in the release since, after continuous breeding, it becomes a self-pollinated line, since during the fourth generation the species of $F_3$ are inbred. Thus it can lead to inbreeding depression, and also natural selection predominates the process. Thus it is not the right option.
-The plants produced in the F6 generation cannot be tested and released since, after a series of breeding experiments are done, it becomes similar to inbreeding and becomes a self-pollinated generation. This can lead to inbreeding depression and also natural selection. Thus it is not the appropriate option.
Therefore, from the given set of options, the most appropriate answer is B. That is, in the pedigree method of hybridization up to $F_3$ generation can be tested and released for cultivation.

Note: The process of hybridization possesses many advantages in agriculture. It helps in increasing the yield. When two genetically dissimilar species are combined to produce the progeny, the best characters among the plants are selected and the unfavorable traits are eliminated.