Choose the correct answer A. B, C or D to fill in the blank.

The unique beauty of the bay with its karsts make it a natural to be added to UNESCO’s World (1) ____ listing. But, it seems the opinions are divided among (2)____.

There are more (3) ____ 1,600 islets in the bay, their limestone worn down by 500 million years of (4) ____ downpours, and topped by thick jungle growth. Some of the islands are hollow, creating (5)_____ caves. Some of the larger islands have their own lakes.

At the centre of the bay there (6) _____ 775 of the formations in an area of just 330 square kilometers - an invitation (7) ____ travelers to board a traditional Vietnamese junk-boat and (8) ____ the bay, it’s islands, caves, and floating villages.

 Some of the islands are hollow, creating (5)_____ caves.