Oestrous cyle is reported in

Options

A. cows and sheep
B. humans and monkeys
C. chimpanzees and gorillas
D. none of these.

Explanation

### Step-by-Step Solution:

1. **Understanding the Oestrous Cycle**: The oestrous cycle is a reproductive cycle found in certain non-primates. It involves physiological and hormonal changes that prepare the female body for reproduction.

2. **Identifying Non-Primate Species**: Non-primates include various mammals that do not belong to the primate order. Examples of non-primates are cows and sheep.

3. **Distinguishing Between Primates and Non-Primates**: Primates include higher mammals such as humans, monkeys, chimpanzees, and gorillas. These animals exhibit a different reproductive cycle known as the menstrual cycle.

4. **Analyzing the Options**: The question provides four options:
- Cows and sheep (non-primates)
- Humans and monkeys (primates)
- Chimpanzees and gorillas (primates)
- None of these

5. **Selecting the Correct Answer**: Since the oestrous cycle is specifically reported in non-primates, the correct answer is **cows and sheep**.

### Final Answer:
The oestrous cycle is reported in **cows and sheep**.

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