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.
I chose b. prepare to host a party or an event.
My Party
I first would buy all my materials at the cheapest price. Then, I would set everything up at my place I am hosting the party or event. Next, I would put up decorations so everyone will admire it. Last but not least, I will get ready with return gifts so everyone will have a good memory of the party I hosted or the event. Finally, I will get ready for everyone to come and hand them flowers as a welcome gift.
To know what to do n there classes