Final answer:
Watermelons have the highest percentage of water among the fruits listed, with about 92% water content. While apples and grapes also have significant water content, they do not surpass watermelons in this aspect.
Step-by-step explanation:
Fruits that contain a high percentage of water include apples (B), grapes (C), and particularly watermelons (D), which are known for their high water content. When comparing these options, watermelons stand out as having the highest percentage of water, making it an excellent choice for hydration. So, the answer to the question Which types of fruit have the highest percentage of water? is C) Watermelons. While apples and grapes also contain a significant amount of water, watermelons are made up of about 92% water, making them the clear leader among these choices.