Final answer:
In hop2 mutants, axial associations form without the formation of synaptonemal complexes due to disrupted recombination nodules, preventing chiasmata and affecting genetic diversity.
Step-by-step explanation:
In hop2 mutants, correct pairing of chromosomes during meiosis is disrupted. The mutation affects the formation of the synaptonemal complex, which is crucial for the pairing and recombination process between homologous chromosomes. Specifically, in hop2 mutants, axial associations are formed, but recombination nodules do not form correctly, leading to a failure to establish the synaptonemal complex and the consequential absence of chiasmata. As a result, normal synapsis and crossover events that lead to genetic diversity are compromised. This would correspond to option d: Correct pairing still occurs, axial associations are formed, but there are no synaptonemal complexes formed.