In frog's kidney, the urea is eliminated by:

Options

A. Glomerular filtration
B. Tubular secretion
C. Both (a) and (b)
D. Tubular absorption

Answer

### Step-by-Step Solution:

1. **Understanding the Frog's Excretory System**:
- Frogs have a specialized excretory system that includes kidneys, which play a crucial role in filtering waste products from the blood.

2. **Role of the Kidney in Excretion**:
- The kidneys of frogs are responsible for the elimination of nitrogenous wastes, primarily urea.

3. **Glomerular Filtration**:
- The process of urea elimination begins in the kidneys at a specific site known as the glomerulus, which is part of the nephron. The glomerulus is surrounded by a structure called Bowman's capsule.

4. **Filtration Process**:
- In the glomerulus, blood enters and undergoes filtration. This process separates waste products, including urea, from the blood. The filtered waste then enters the Bowman's capsule.

5. **Reabsorption and Secretion**:
- After filtration, the kidneys also perform reabsorption (where useful substances like glucose and amino acids are taken back into the bloodstream) and tubular secretion (where additional wastes and excess ions are secreted into the urine).

6. **Conclusion**:
- The correct answer to the question "In frog's kidney, the urea is eliminated by" is through the process of glomerular filtration, specifically in the glomerulus and Bowman's capsule.

### Final Answer:
In frog's kidney, the urea is eliminated by glomerular filtration.

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