The embedding of _______X_____ in the _____Y____ of uterus is called implantation. Select the correct option for X and Y.

Options

A. `{:(X,Y),("Blastocyst","Endometrium"):}`
B. `{:(X,Y),("Blastocyst","Myometrium"):}`
C. `{:(X,Y),("Trophoblasts","Myometrium"):}`
D. `{:(X,Y),("Trophoblasts","endometrium"):}`

Answer

To solve the question regarding the embedding of X in the Y of the uterus called implantation, we need to identify the correct terms for X and Y.

### Step-by-Step Solution:

1. **Understanding Implantation**:
- Implantation is the process where a developing embryo attaches itself to the wall of the uterus. This is a crucial step in the establishment of pregnancy.

2. **Identifying X**:
- The term X refers to the structure that embeds itself in the uterine wall. In human development, this structure is known as the **blastocyst**. The blastocyst is formed after the zygote undergoes several divisions and develops into a hollow ball of cells.

3. **Identifying Y**:
- The term Y refers to the specific layer of the uterus where the blastocyst embeds itself. The uterus has three layers: the perimetrium, myometrium, and endometrium. The correct layer where implantation occurs is the **endometrium**. This is the inner lining of the uterus that thickens in preparation for a potential pregnancy.

4. **Final Answer**:
- Therefore, the embedding of **blastocyst** in the **endometrium** of the uterus is called implantation.

### Conclusion:
The correct option for X and Y is:
- X = Blastocyst
- Y = Endometrium