`F_1` generation means:

Options

A. first flowering generation
B. first fertile generation
C. first filial generation
D. first seed generation

Answer

To answer the question "What does F1 generation mean?", we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Generations in Genetics**:
- In genetics, the term "generation" refers to the offspring produced from a particular set of parental organisms.

2. **Defining F1 Generation**:
- The F1 generation specifically refers to the first generation of offspring that results from a cross between two genetically distinct parent plants or organisms.

3. **Genetic Distinction**:
- The parents of the F1 generation are typically chosen because they have different traits or characteristics, which allows for the study of inheritance patterns in their offspring.

4. **Full Form of F1**:
- The "F" in F1 stands for "filial," which is derived from the Latin word "filius," meaning "son." Therefore, F1 stands for "first filial generation."

5. **Identifying the Correct Option**:
- Among the options provided:
- A) First flowering generation
- B) First fertile generation
- C) First filial generation
- D) First seed generation
- The correct answer is C) First filial generation.

6. **Conclusion**:
- The F1 generation is crucial in genetics as it allows researchers to observe the traits inherited from the parent organisms and understand the principles of heredity.

### Final Answer:
The F1 generation means "first filial generation."

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