1. The appearances of fireflies at dusk is an example of a circadian rhythm because it's happens daily. The correct option among all the options that are given in the question is the third option or option "c".
2. During migration, animals undertake a seasonal movement. The correct option among all the options that are given in the question is the first option or option "a".
The solar system is considered a natural system because it was made and controlled by natural forces, meaning, it was never influenced with human creations. It is considered as one of the products of the phenomenon of the physical world. Hope this answer helps you.
The recombinant offsprings are normally the offsprings containing a combination of the parents allele, result in a genotype that differs from both parents genotype. The phenotype May be different as well although it is likely that the phenotype could be the same as the parents, as seen in the case of heterozygous dominant having the same phenotype as homozygous dominant.
Due to the definition of the central dogma, another way of putting it is that the central dogma follows the flow of information from DNA to protein.