Embryo sac is to ovule as is to an anther.

Options

A. Stamen
B. Filament
C. Pollen grain
D. Androecium

Explanation

To solve the analogy "Embryo sac is to ovule as ___ is to anther," we need to understand the relationship between the terms involved.

1. **Understanding the Terms**:
- The **embryo sac** is the female gametophyte found within the **ovule**. It contains the egg cell and is crucial for fertilization.
- The **anther** is part of the **stamen**, which is the male reproductive structure in flowers. The anther produces **pollen grains**, which are the male gametophytes.

2. **Establishing the Relationship**:
- In the analogy, the relationship is that the embryo sac is a structure found within the ovule, just as the pollen grain is a structure found within the anther.
- Therefore, we need to identify what is to the anther as the embryo sac is to the ovule.

3. **Identifying the Correct Answer**:
- The options provided are:
- A) Stamen
- B) Filament
- C) Pollen grain
- D) Androsium
- Since the pollen grain is produced in the anther and is analogous to the embryo sac in the ovule, the correct answer is **C) Pollen grain**.

4. **Final Answer**:
- Thus, the complete analogy is: "Embryo sac is to ovule as pollen grain is to anther."