D. Polar regions receive less solar energy and heat per unit area than tropical regions
Less direct sunlight means that there is less concentration of direct solar rays. This would influence temperature and would ultimately create weather, and since this pattern continues of switching direct ray latitudes, this would create climate zones all over the Earth, and similar ones with similar latitude and terrain.
The answer is vascular plants.
Vascular plants have <span>specialized tissues that can transport fluids - vascular tissue. This tissue consists of</span><span> xylem and phloem. Xylem transports water and minerals from the root to the upper parts of the plant. Phloem transports food and nutrients from the leaves, where they are produced, to the growing or storage parts of the plants. </span>
<span>A person must inherit two copies of a defective CF gene -- one copy from each parent -- to have the disease. People who inherit only one copy are considered CF carriers and do not have the disease, but they can pass their copy of the defective gene on to their children.</span>