Certain plants need to be exposed to low temperature ' so as to hasten flowering later in life. This treatment is known as

Options

A. stratification
B. scarification
C. vernalisation
D. photoperiodism

Answer

To solve the question regarding the treatment that certain plants need to undergo to hasten flowering later in life through exposure to low temperatures, we can analyze the options provided:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a specific treatment that involves exposing plants to low temperatures to promote flowering.

2. **Evaluating the Options**:
- **Option 1: Stratification**: This term refers to the vertical layering of a habitat and is not related to flowering processes. Therefore, this option is incorrect.
- **Option 2: Scarification**: This process involves altering the seed coat to encourage germination, not flowering. Hence, this option is also incorrect.
- **Option 3: Vernalization**: This is the process where plants are exposed to prolonged cold temperatures to induce flowering. It is specifically aimed at hastening the flowering process in certain plants. This option is correct.
- **Option 4: Photoperiodism**: This term refers to how organisms respond to changes in light and darkness duration. It does not relate to low-temperature exposure for flowering. Therefore, this option is incorrect.

3. **Conclusion**: Based on the analysis of the options, the correct answer is **Vernalization**, as it specifically refers to the induction of flowering in plants through exposure to cold temperatures.

### Final Answer:
The treatment that certain plants need to be exposed to low temperatures to hasten flowering later in life is known as **Vernalization**.

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