Final answer:
The third step of the V(D)J recombination is the cleavage of the recombination signal sequences, which is crucial for the generation of diverse antibodies in B cells.
Step-by-step explanation:
The question refers to the V(D)J recombination process that takes place during the maturation of B cells. V(D)J recombination is a mechanism of genetic recombination that occurs in the immune system, which allows B cells to generate a diverse array of antibodies. Step 3 of this process, according to the options provided, is C) Cleavage of recombination signal sequences. This step follows the recognition of recombination signal sequences (RSS) by the RAG1/2 complex and precedes the formation of the hairpin structure. During cleavage, the DNA between the V(D)J coding segments and the RSS is cut, allowing for the segments to be joined together.