Read the given passage carefully and answer the questions that follow:-
During his journey, Darwin went to Galapagos Islands. There he observed an amazing diversity of creatures. Of particular interest ,small black birds called Darwin's Finches amazed him. He realized that there were many varieties of finches in the same island. All the varieties, he conjectured, evolved on the island itself. From the original seed-eating features, many other forms with altered beaks arose, enabling them to become insectivorous and vegetarian finches. This process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called adaptive radiation. Darwin’s finches represent one of the best examples of this phenomenon. Another example is Australian marsupials. A number of marsupials, each different from the other (Figure 6.6) evolved from an ancestral stock, but all within the Australian island continent. When more than one adaptive radiation appeared to have occurred in an isolated geographical area (representing different habitats), one can call this convergent evolution. Placental mammals in Australia also exhibit adaptive radiation in evolving into varieties of such placental mammals each of which appears to be ‘similar’ to a corresponding marsupial (e.g., Placental wolf and Tasmanian wolf-marsupial).The essence of Darwinian theory about evolution is natural selection. Nature selects for fitness. One must remember that the so-called fitness is based on characteristics which are inherited. Hence, there must be a genetic basis for getting selected and to evolve. Another way of saying the same thing is that some organisms are better adapted to survive in an otherwise hostile environment. Adaptive ability is inherited. It has a genetic basis. Fitness is the end result of the ability to adapt and get selected by nature.

What does the term "fitness" refer to in the context of natural selection?

The ability to survive and reproduce under specific conditions

The correct answer is Option (2) –The ability to survive and reproduce under specific conditions

In evolutionary biology, fitness is a measure of an organism's ability to survive and reproduce in its environment. The concept of fitness is central to the theory of natural selection, which was first articulated by Charles Darwin. Fitness is not about the physical strength of an organism, how fast it can move, or the sheer number of offspring it can produce; rather, it is about how well an organism's traits enable it to thrive in its specific environment and contribute to the next generation's gene pool.

An organism must be able to live long enough to reproduce. Traits that enhance an organism's ability to avoid predators, find food, and resist diseases contribute to its survival.

The ultimate measure of fitness is reproductive success. An organism's fitness is reflected in the number of offspring it produces that survive to reproductive age.

Fitness is about passing genes to the next generation. Traits that improve an organism's reproductive success become more common in the population over generations.

Therefore, fitness in the context of natural selection is about the capacity to survive, reproduce, and pass on genes in a given environment, ensuring that the advantageous traits continue in future generations.