Natural Selection:
Natural selection is the process by which certain traits or characteristics become more or less common in a population over time. It is the primary mechanism of evolution and occurs as a result of the differential survival and reproduction of individuals with favorable traits. Here are some key points about natural selection:

1. Differential Survival: Individuals with traits that are advantageous for their environment are more likely to survive and reproduce, passing on their genes to the next generation.

2. Adaptation: Through natural selection, organisms become adapted to their environment. This means that their traits are well-suited for their specific ecological niche.

3. Environmental Pressures: Natural selection is driven by the pressures and challenges posed by the environment. These pressures can include factors such as predation, competition for resources, and changes in climate.

4. Random Variation: Natural selection acts on the genetic variation that exists within a population. This variation arises through random mutations, genetic recombination, and gene flow.

5. Gradual Process: Natural selection is a gradual process that occurs over many generations. It leads to the accumulation of advantageous traits and the elimination of disadvantageous ones.

Sexual Selection:
Sexual selection is a specific type of natural selection that operates on traits related to mating success. It occurs when individuals within a population differ in their ability to attract mates and reproduce. Here are some key points about sexual selection:

1. Reproductive Success: Sexual selection focuses on traits that increase an individual's chances of mating and producing offspring. These traits may not necessarily be advantageous for survival but can enhance reproductive success.

2. Intrasexual Selection: Intrasexual selection occurs when individuals of one sex compete with each other for access to mates. This competition can involve direct physical combat or other forms of competition, such as displays or vocalizations.

3. Intersexual Selection: Intersexual selection occurs when individuals of one sex choose mates based on specific traits or characteristics. This can lead to the evolution of elaborate displays, ornaments, or behaviors that are attractive to the opposite sex.

4. Sexual Dimorphism: Sexual selection often leads to the development of sexual dimorphism, where males and females of a species have distinct physical or behavioral differences. These differences are often related to mating and reproduction.

5. Evolutionary Trade-offs: Sexual selection can sometimes result in traits that are costly or detrimental to survival. For example, the elaborate tail feathers of male peacocks may attract predators but are favored by female choice.

Relationship between Natural Selection and Sexual Selection:
Sexual selection is a type of natural selection because it operates on heritable traits and leads to changes in the genetic composition of a population over time. It is a specific mechanism within natural selection that focuses on traits related to reproduction. In other words, sexual selection is a subset of natural selection that specifically deals with mate choice and competition for mates.

Option A