Question

Which of the following is the most important cause for animals and plants being driven to extinction?
A. Habitat loss and fragmentation
B. Drought and floods
C. Economic exploitation
D. Alien species invasion

Answer 1

Extinction means the permanent disappearance of a species or a population of a species or a population from the earth.

Complete answer:
Evolutionary studies and fossil studies have developed recently. It is seen that there are many organisms which have become extinct from the earth. The high rate of species extinction is mainly due to human activities. Humans are the main cause for the disappearance of many species on the earth.
Among the different reasons, loss of habitat stands the most crucial cause of driving organisms to extinction. The natural habitats of organisms mainly the tropical rainforests are now destroyed and the trees are cut due to the cultivation of economically significant crops and are changed into grasslands for raising cattle.
It is found that in the area where habitat loss is there the organism living in that area will face the threat of extinction due to the lack of food resources and shelter. Mainly many of the species require large territories and have migratory needs which are badly affected by habitat loss and fragmentation. It is the main factor for the extinction of plants and animals.
Each and every human being depends on food and shelter but when needs lead to greed it is called overexploitation. Because of overexploitation by humans Steller’s sea cow has undergone extinction.
Whenever the alien species are introduced for the particular purpose, it may turn out invasive and can decrease the indigenous species it is called alien species invasion. The Nile Perch in Lake Victoria leads to extinction for 250 species of cichlid fish in the lake.

Hence, the correct answer is option (A).

Note: Habitat loss is the important reason for the extinction in plants and animals. It is mostly in the tropical rainforest. The earth land surface covering the rainforest is now reduced to less than 5% from 15%.