C. because you may only have one manipulated variable to be able to know the responding variable.
Where air pollution is not especially severe, predators have much more impact on leaf-beetle populations than parasites do
In my opinion, it is harmful. As said in the text “The sickle cell mutation causes hemoglobin to become less soluble and stick together when blood oxygen levels are low. In turn, red blood cells with clumped hemoglobin become sickle-shaped, which can lead to pain, swelling of the hands and feet, frequent infections, and eye problems.” So basically, (in my own words) when blood oxygen levels are low, the sickle cell mutation makes hemoglobin less soluble, causing it to cling together. As a result, sickle-shaped red blood cells form, causing discomfort, swelling in the hands and feet, frequent infections, and vision issues.
The main reason why it would be hard to establish a large area of protected land is the poor representation of habitats.
<h3>What is a Protected Land?</h3>
This refers to the place or area that protects the biodiversity of habitats and organisms in the area.
Hence, we can see that the two benefits provided by protected lands such as national parks are:
- They safeguard biodiversity
- They preserve important habitats
The main way in which buffer zones help mitigate the problems of overcrowding, development, pollution, and invasive species in national parks is helping to separate critical habitats from each other due to their neutrality.
Read more about habitats here:
brainly.com/question/22705233
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