The idea that viruses originated as genetic material that was able to move within a genome, eventually exiting a cell and entering another is the hypothesis.

a. progressive

b. recessive

c. coevolution

d. regressive

.

A. Progressive

Explanation:

Origin of viruses is explained variously. According to one hypothesis, viruses are thought to be originated from mobile genetic elements. This is also called a progressive hypothesis of the origin of viruses.

According to this hypothesis, some sequences from the genomes acquired the ability to move from one locus to another locus of genome. Gradually, these mobile genetic elements acquired the ability to move between different cells and led to the evolution of viruses.

fertilization, pictured in figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. the egg and sperm each contain one set of chromosomes. to ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. in mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. when a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. in placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in figure 24.23b. the fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. the nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.

explanation:

you did not attach the discourse, but i assume it to be the discourse on the origin and basis of inequality among men (the original titile in french is: "discours sur l'origine et les fondements de l'inégalité parmi les hommes"), also know as "second discourse". in this discourse, jean-jacques rousseau emphasizes that private property is the basis of all inequalities.

therefore, what enabled the old regime to maintain as long as it did was private property.