Final answer:
a. The tropical zone has the most potential for afforestation globally due to its high growth rates and biodiversity.
Step-by-step explanation:
The latitudinal zone that has the most potential for afforestation globally is the a. tropical zone. This is because the tropical zone has high growth rates due to the favorable climate conditions, including consistent warmth and precipitation throughout the year.
In addition, the tropical zone is known for its high biodiversity, which means there is a wide variety of plant and animal species that can be introduced during afforestation efforts. This biodiversity helps create a more resilient and sustainable forest ecosystem.
Therefore, the combination of favorable climate conditions and high biodiversity make the tropical zone the most suitable for afforestation globally.