Well saying dunno is an error in formal/academic writing. In academic writing you would have to write, i do not know, though.
Answer:
Denmark's growth in the 16th century
Explanation:
The paragraph is about how the population of Denmark grew in the early to mid 16th century.
B. Everyone stands and removes their hats when the American flag passes.
It helps to explain the idea in the 4th paragraph about why organic foods often cost more than non organic foods.
It supports the idea in the 1st paragraph that genetically modified foods have the potential to cause health issues.