Question

according to source 8, what was a major cause of the global spread of humans?
the use and control of fire
extinction of some animal species
population growth
land bridges

Explanation:

To determine the major cause of the global spread of humans, we analyze each option:

• "The use and control of fire" is more related to human development in a local or technological sense, not directly to global spread.
• "Extinction of some animal species" is an effect or result, not a cause of human spread.
• "Population growth" can lead to the need to spread, but land bridges (geographical features) allowed humans to migrate across continents and spread globally. For example, land bridges like the Bering Land Bridge enabled human migration to the Americas.
• "Land bridges" provided physical pathways for human migration between different landmasses, facilitating the global spread of human populations.

Answer:

D. Land bridges (assuming the options are labeled A - D with D being Land bridges; if the original labeling was different, adjust the identifier, but based on the options, the correct one is the option with "Land bridges")