Question

many diseases transmitted by vectors lead to the death of millions of people in the world. which best explains why african countries are harder hit than other regions of the world?
a. increased ecosystem changes
b. increased climatic variations
c. increased pressure from human activities
d. increased number of insects

Explanation:

To determine why African countries are harder hit by vector - borne diseases, we analyze each option:

• Option A: Ecosystem changes are not the primary reason for the higher impact of vector - borne diseases in Africa compared to other regions. Ecosystem changes can affect disease transmission, but it is not the most significant factor here.
• Option B: Climatic variations are not the main driver. While climate can influence vector populations, the key factor related to human - vector interactions in Africa is more about human activities.
• Option C: In African countries, there is increased pressure from human activities such as deforestation, urbanization, and agricultural expansion. These activities disrupt natural habitats, bring humans into closer contact with disease vectors, and also affect the availability of resources for disease prevention and control. This is a major factor contributing to the higher burden of vector - borne diseases.
• Option D: The "increased number of insects" is a simplistic view. The distribution and interaction of disease - carrying insects with human populations are more complex and are largely driven by human activities rather than just a general increase in insect numbers.

Answer:

C. increased pressure from human activities