"How beautiful those hills are!"
It is an example of :

Question

"How beautiful those hills are!" 
 It is an example of :

Accepted Answer

The sentence "How beautiful those hills are!" is an example of an exclamatory sentence. Let's explore why Option 2 is the correct choice and why the other options are incorrect.

1. **Explanation for Option 2 (Exclamatory sentence):**
   - An exclamatory sentence is used to express strong emotion or excitement. It often begins with words like "how" or "what" and ends with an exclamation mark. In this sentence, the speaker is expressing admiration and wonder at the beauty of the hills, which is a strong emotional response. The use of the exclamation mark at the end further emphasizes the exclamatory nature of the sentence. Therefore, Option 2 is the correct answer.

2. **Why Option 1 (Imperative sentence) is incorrect:**
   - An imperative sentence is used to give a command, make a request, or offer advice. It typically starts with a verb and does not usually include a subject. For example, "Look at those hills" is an imperative sentence. The given sentence does not instruct or command anyone to do anything; instead, it expresses an emotion, which is why it is not an imperative sentence.

3. **Why Option 3 (Interrogative sentence) is incorrect:**
   - An interrogative sentence is used to ask a question and typically ends with a question mark. It often begins with words like "who," "what," "where," "when," "why," or "how." Although the sentence starts with "how," it does not pose a question but rather expresses an emotion. Therefore, it is not an interrogative sentence.

4. **Why Option 4 (Rhetorical question) is incorrect:**
   - A rhetorical question is a question asked to make a point rather than to elicit an answer. It often implies its own answer or is used for persuasive effect. The given sentence is not structured as a question and does not seek to make a point through a question format. Instead, it directly expresses admiration, making it an exclamatory sentence rather than a rhetorical question.

In conclusion, the sentence "How beautiful those hills are!" is best categorized as an exclamatory sentence due to its expression of strong emotion and the use of an exclamation mark, which aligns perfectly with the characteristics of Option 2.