Which of the following pairs is wrong ?

Options

A. a) Uricotelic-Birds
B. b) Ureotelic-Insects
C. c) Ammonotelic-Tadpole
D. d) Ureotelic-Elephant

Explanation

To solve the question of which pair is wrong regarding the classification of animals based on their nitrogenous waste excretion, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Nitrogenous Waste Types**:
- There are three main types of nitrogenous wastes produced by animals: ammonia, urea, and uric acid.
- Animals are classified based on the type of nitrogenous waste they excrete:
- **Ammonotelic**: Excrete ammonia (e.g., aquatic animals like fish).
- **Ureotelic**: Excrete urea (e.g., mammals, amphibians).
- **Uricotelic**: Excrete uric acid (e.g., birds, reptiles).

2. **Analyze Each Option**:
- **Option A**: Uricotelic animals are birds. This is correct because birds excrete uric acid.
- **Option B**: Ureotelic animals are insects. This is incorrect because most insects are uricotelic, not ureotelic.
- **Option C**: Ammonotelic animals are tadpoles. This is correct as tadpoles live in water and excrete ammonia.
- **Option D**: Ureotelic animals are elephants. This is correct because elephants, being mammals, excrete urea.

3. **Identify the Incorrect Pair**:
- From the analysis, Option B is the only incorrect pair since it states that insects are ureotelic, while they are primarily uricotelic.

### Conclusion:
The wrong pair is **Option B: Ureotelic insects**.

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