Hydrogen would be the answer to this.
Because they play important roles in the environment, take the food chain for example. animals continuously convert energy all the way up until a human eats. also, decomposers are important too because the return nutrients to the ground, like mushroom, fungi, and bacteria
Water and minerals are absorbed into the blood in the colon of the large intestine.
Answer:
C) Unrestricted whaling could lead to their extinction.
Explanation:
The whaling is a process of hunting and killing whales so as to get the meat, oil and whalebone so that they can be sell it out commercially. The trade of whale resources was firstly in France and Spain in 16th century but they have been spread worldwide. However, the conservation groups worldwide are pushing the restriction on whaling as unrestricted whaling can lead to complete extinction of the whale species from the Earth.