Daniel likes to do something to protect the environment in his daily life. Next Sunday is his friend’s birthday. He is going to buy some gifts online for his friend. Now he is visiting the following website for some information about gifts.

Welcome to Nature Posters - the world's largest collection(收集) of nature posters and fine art prints! We make a donation to help the environment when each nature poster is sold through this website! Please tell your friends about us, and remember us when you are gift shopping.

Daniel chose the following two beautiful pictures as gifts from the website:
          
Parrots in Blue: $5.99                    Sharks: $7.99
Nature Posters is a website ________.

A．to help people plan their birthday parties

B．only to provide information about nature

C．to tell people how to buy birthday presents

D．to help protect nature by selling posters or prints

Daniel should pay ________ for his gifts.

A．$5.99

B．$13.98

C．$7.99

D．$2.00