I believe the correct answer is to help the reader visualize a view where water and sky are difficult to tell apart.
The author is trying to portray an image where the water and the sky are somehow blending into each other - you can't tell where one ends and the other one begins, because both items are colored similarly - various shades of blue.
Playing basketball helps to improve motor coordination, flexibility, and endurance. It also encourages speed, agility, and strength. These skills are shown to have a positive effect on promoting a healthy body weight and encouraging more physical activity, which can enhance cardiorespiratory fitness and self-esteem Health benefits of basketball
burn calories (an hour of basketball can burn 630–750 calories) build endurance. improve balance and coordination. develop concentration and self-discipline.
