the moderate temperatures of islands throughout the world has much to do with waters:

A. hgih evaporation rate.
B. vast supply of thermal enerygy.
C. poor conductivity
D.high specific heat capacity.

d. Sea water stores heat.

The moderate temperatures of islands throughout the world are primarily due to the high specific heat capacity of water.

To determine the answer to this question, let's go through each option and see which one is most likely to be responsible for the moderate temperatures of islands throughout the world.

A. High evaporation rate: While high evaporation rates can lead to cooling effects, it doesn't necessarily contribute to moderate temperatures. Evaporation is the process of water turning into vapor, and it takes place when water is heated. While islands are surrounded by water, it doesn't necessarily mean that the high evaporation rate is the main reason for moderate temperatures.

B. Vast supply of thermal energy: While islands are surrounded by water and thus have access to thermal energy, the vast supply of thermal energy alone may not directly result in moderate temperatures. This option is not the most likely one.

C. Poor conductivity: Poor conductivity refers to the inability of a material to transfer heat. If the surrounding waters have poor conductivity, it would mean that they are not efficient in transferring heat to the islands. However, poor conductivity alone doesn't explain why the temperatures are moderate on the islands.

D. High specific heat capacity: Specific heat capacity refers to the amount of heat energy required to raise the temperature of a substance. Water has a high specific heat capacity compared to many other materials. This means that water can absorb a significant amount of heat without experiencing a significant rise in temperature. Islands surrounded by water benefit from this property, as the water can absorb excess heat and prevent drastic temperature changes. Thus, the high specific heat capacity of water is the most likely reason for the moderate temperatures of islands throughout the world.

Therefore, the correct answer is D. High specific heat capacity.