The correct answer is option B, that is, diminished food supply.
Some of the animals move to comparatively short distances in search of food or more favorable breeding or living conditions. However, the majority of animals, which migrate do so in order to find more habitable conditions and food. The phenomenon can be witnessed in almost all the prime animal groups like mammals, birds, amphibians, fish, reptiles, crustaceans, and insects.
About 71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. But water also exists in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers, and even in you and your dog.
<span>When the diaphragm contracts and moves lower, the chest cavity enlarges, reducing the pressure inside the lungs. To equalize the pressure, air enters the lungs. When the diaphragm relaxes and moves back up, the elasticity of the lungs and chest wall pushes air out of the <span>lungs. hope this helps</span></span>