Which of the following sentences demonstrates clear, parallel structure? a) our trip to the beach was fantastic and we did many enjoyable things including: playing in the sand, we ate at some delicious restaurants, and were able to see the sun set from a boat off shore. b) our trip to the beach was fantastic and we did many enjoyable things including: playing in the sand, eating at delicious restaurants, and watching the sunset from a cruise ship. c) our trip to the beach was fantastic and we did many enjoyable things including: playtime in the sand, we ate at some delicious restaurants, and we saw pretty sunsets. d) our trip to the beach was fantastic and we did many enjoyable things including: playing in the sand, eating at delicious restaurants, and we had a really nice time riding out into the sunset on a cruise ship.