Sentence 5 talks about looking for alternate energy sources but doesn't specifically mention solar energy so it is wrong. Sentence 10 says that solar energy is a "significant development" but it doesn't provide specific evidence so it is also not correct. Sentence 6 is the best answer - it shows that it is already being used and it has the potential to be used even more.
1.-A. A trip to the ocean can be a relaxing escape from the everyday pressures of life.1.-B. You should always be careful to avoid overexposure to the sun at the beach.
