C.sugar is often added to dishes

=> vì trong đoạn văn 2 có câu ( Southerners are favored of sugar; they add sugar in almost dishes.) 

Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the following questions. Vietnamese food culture varies by regions from the north to the south. In Northern Vietnam, food is characterized by light and balanced. Northern Vietnam is seen to be the cradle of Vietnamese cuisine with many notable dishes like Pho, Bun Rieu, Bun Thang, Bun Cha, Banh Cuon, etc. Then, food culture in Northern Vietnam became popular in Central and Southern Vietnam with suitable flavors in each regions. The regional cuisine of Central Vietnam is famous for its spicy food. Hue cuisine is typical Central Vietnam’s food culture. Food in the region is often used with chili peppers and shrimp sauces, namely, Bun Bo Hue, Banh Khoai, Banh Beo, etc. In Southern Vietnam, the warm weather and fertile soil create an ideal condition for planting a variety of fruit, vegetables and livestock. Thus, food in the region is often added with garlic, shallots and fresh herbs. Particularly, Southerners are favored of sugar; they add sugar in almost dishes. Some signature dishes from Southern Vietnam include Banh Khot and Bun Mam.

Question. In Southern Vietnam, __________.

A.fresh herbs are always used in cooking

B.people love sweet food

C.sugar is often added to dishes

D.the warm weather makes it hard to plant fruit and vegetables