Which one of the following is back cross?

Options

A. `F1 xx F1`
B. `F1 xx` Recessive parent
C. `F1xx` Dominant parent
D. `F1 xx` Any parent

Answer

### Step-by-Step Solution:

1. **Understanding Back Cross**:
- A back cross is a breeding method where a hybrid organism (usually the F1 generation) is crossed with one of its parents or an individual genetically similar to its parent. This is done to evaluate the genetic traits of the offspring and to identify the genetic similarity to the parent.

2. **Purpose of Back Cross**:
- The main purpose of performing a back cross is to determine the genetic makeup of the hybrid offspring. By crossing the F1 hybrid with one of its parents, researchers can observe which traits are expressed and how closely the offspring resemble the parent in terms of genetic traits.

3. **Identifying the Correct Option**:
- In the context of the question, we need to identify which option represents a back cross. The correct answer will involve crossing the F1 progeny with one of its parent organisms.

4. **Analyzing the Options**:
- The options provided will typically include various combinations of parental and hybrid crosses. The option that states that the F1 progeny is crossed with a parent (or a genetically similar individual) is the correct representation of a back cross.

5. **Conclusion**:
- After analyzing the options, the last option is identified as the correct one because it clearly states that the F1 progeny is crossed with a parent, which aligns with the definition of a back cross.