This morning I went to a nearby food store to buy some breads. After the man in the store packing the bread in a small bag for me, I began to walk home with bag in my hand. On the way I met my next-door neighbor, Miss Wang, that was walking her dog .We greeted with each other and begin to talk about the weather. As we were talking, his dog came up at the bag in my hand though the bread gave off a delicious smell. As a result, some of the bread fell to the ground or the dog began to enjoy it. Five minutes late, I was back at the store to buy bread again.

我国减排压力仍然巨大，我国二氧化碳排放总量进一步上升，是世界上（）碳排放国。

A.第一大

B.第三大

C.第四大

D.第二大