What sentence is written using formal style?

A. Changes in the world's climate affect weather patterns, and this increases the frequency of drought and floods.
B. Some of the hugest amounts of carbon emissions are created by farmers who don't follow good farming practices.
C. I mean, farmers should obviously support climate change actions because their farms are at stake.
D. I have never been able to understand why so many people cannot grasp the urgency of climate change.

A. Changes in the world's climate affect weather patterns, and this increases the frequency of drought and floods.

The sentence written using formal style is:

A. Changes in the world's climate affect weather patterns, and this increases the frequency of drought and floods.

To determine which sentence is written in a formal style, we need to examine the language and structure used. Formal style typically follows grammatical rules, avoids slang or colloquial language, and uses a serious and professional tone.

Let's analyze each sentence:

A. "Changes in the world's climate affect weather patterns, and this increases the frequency of drought and floods." - This sentence uses proper grammar, avoids slang, and maintains a serious tone. It presents information objectively, making it a good example of a sentence written in a formal style.

B. "Some of the hugest amounts of carbon emissions are created by farmers who don't follow good farming practices." - This sentence contains informal language with the word "hugest" and the phrase "good farming practices." It also lacks a professional tone and would be more suited for casual conversations.

C. "I mean, farmers should obviously support climate change actions because their farms are at stake." - This sentence includes the phrase "I mean," which is often used in informal conversation. It also uses a less formal tone with the words "obviously" and "at stake," and lacks proper grammar and structure.

D. "I have never been able to understand why so many people cannot grasp the urgency of climate change." - This sentence, similar to option C, includes personal pronouns like "I" and expresses a subjective opinion. It also uses a less formal tone with phrases like "never been able to understand" and "so many people cannot grasp."

Based on the analysis, sentence A is written in a formal style.