Correct answer: B. oxygen
Humans would not be able to breathe and sound would not be able to travel also there would not be any life
~in which there would be no plants because humans breathe out carbon dioxide and if there are no humans then plants won’t be able to consume carbon dioxide
Question:
<em>What is Darwin’s theory of the origin of species?</em>
Answer:
<em>The theory of evolution by natural selection, first formulated in Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits.</em>
Hope this helps!
Out of the following given choices;
(1) an increase in the number of clams
(2) a decrease in the number of water plants
(3) an increase in the number of crabs
(4) a decrease in the number of crayfish
The answer is D. Crayfish are are freshwater crustaceans resembling small
lobsters. Clams and crabs are found in marine waters. Most crayfish cannot
tolerate polluted water. Crayfish feed on animals and plants, either living or
decomposing, and detritus, therefore a decrease in small invertebrates in the river
would decrease their food source thence
consequently affect their numbers.
