Consider the given statements and choose the correct option
(a) many bony fishes , tadpole larva of frog and terrestrial insects are ammonotelic in nature
(b) in frog kidneys are mesonephric
(c) GFR falls - activation of JG cells - release rennin - GFR normal
(d) NaCI is transported by the ascending limb of Henles loop which is exchanged with the ascending portion of visa recta

Options

A. `{:(a,b,c,d),("true","true","true","false"):}`
B. `{:(a,b,c,d),("false","true","false","false"):}`
C. `{:(a,b,c,d),("true","false","false","true"):}`
D. `{:(a,b,c,d),("false","true","true","false"):}`

Answer

To solve the question, we will analyze each statement one by one to determine which ones are correct.

### Step-by-Step Solution:

1. **Statement (a)**: "Many bony fishes, tadpole larva of frog, and terrestrial insects are ammonotelic in nature."
- **Analysis**: Ammonotelic organisms excrete ammonia as their primary nitrogenous waste. While many bony fishes and tadpole larvae are indeed ammonotelic, terrestrial insects are typically uricotelic, meaning they excrete uric acid. Therefore, this statement is **false**.

2. **Statement (b)**: "In frog, kidneys are mesonephric."
- **Analysis**: Frogs possess mesonephric kidneys during their adult stage. This statement is **true**.

3. **Statement (c)**: "GFR falls - activation of JG cells - release renin - GFR normal."
- **Analysis**: This statement describes the physiological response to a decrease in the glomerular filtration rate (GFR). When GFR falls, the juxtaglomerular (JG) cells are activated, leading to the release of renin, which helps to restore GFR to normal levels. However, it is important to note that renin is an enzyme, not a hormone. Despite this minor detail, the overall process described is correct. Thus, this statement is **true**.

4. **Statement (d)**: "NaCl is transported by the ascending limb of Henle's loop which is exchanged with the ascending portion of vasa recta."
- **Analysis**: The ascending limb of the loop of Henle does transport NaCl, but it does not exchange it with the ascending portion of the vasa recta. The vasa recta is involved in the countercurrent exchange mechanism but does not directly exchange NaCl in this manner. Therefore, this statement is **false**.

### Conclusion:
- The correct options are **(b)** and **(c)**.

### Final Answer:
The correct option is **(b)** and **(c)**.

---