Shivering in cold is a method for :

Options

A. preventing radiation of heat from the body
B. production of heat by bringing more blood of the body surface
C. production of heat by muscular contraction
D. None of these .

Answer

To solve the question "Shivering in cold is a method for:", we will analyze the options given and understand the physiological process involved in shivering.

### Step-by-Step Solution:

1. **Understanding Shivering**:
- Shivering is a physiological response that occurs when the body is exposed to cold temperatures. It is characterized by rapid, involuntary muscle contractions.

2. **Identifying the Muscle Type**:
- The muscles involved in shivering are striated muscles (skeletal muscles), which are responsible for voluntary movements but can also react involuntarily in response to cold.

3. **Purpose of Shivering**:
- The primary purpose of shivering is to generate heat. When the muscles contract rapidly, they produce heat as a byproduct of metabolism, which helps to warm the body.

4. **Analyzing the Options**:
- **Option 1**: Preventing radiation of heat from the body - This is not correct because shivering does not primarily prevent heat loss; rather, it generates heat.
- **Option 2**: Reduction of heat by bringing more blood to the body surface - This is also incorrect as shivering does not involve blood flow regulation; it focuses on heat production.
- **Option 3**: Reduction of heat by muscular contraction - This option is misleading; shivering actually increases heat through muscular contraction, not reduces it.
- **Option 4**: None of these - This could be a consideration if none of the options accurately describe shivering.

5. **Correct Answer**:
- The correct interpretation is that shivering is a method of generating heat through muscular contraction. Therefore, while the wording in option 3 may seem confusing, it is the closest to the truth since it involves muscular contraction to produce heat.

### Final Answer:
Shivering in cold is a method for **generating heat by muscular contraction**.