Which of the following statements is correct ?
(A) Mycoplasma has no cell wall
(B) Viruses can multiply only when they are present inside the living cell.
(C) True sexuality s not found in bacteria
(D) Mycoplasma can not survive without `O_(2)`

Options

A. A, B,C & D
B. A,B,D
C. A, B, C
D. C & D

Answer

To determine which of the statements is correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement (A): Mycoplasma has no cell wall.**
- Mycoplasma is a type of bacteria that is unique because it lacks a cell wall. This characteristic allows it to be flexible and invade host cells more effectively. Therefore, this statement is **correct**.

2. **Statement (B): Viruses can multiply only when they are present inside the living cell.**
- Viruses are obligate intracellular parasites, meaning they cannot reproduce or carry out metabolic processes outside of a host cell. They require the machinery of a living cell to replicate. Thus, this statement is also **correct**.

3. **Statement (C): True sexuality is not found in bacteria.**
- Bacteria primarily reproduce asexually through binary fission. While some bacteria can exchange genetic material through processes like conjugation, transformation, or transduction (which can be considered forms of genetic recombination), they do not engage in true sexual reproduction as seen in higher organisms. Therefore, this statement is **correct**.

4. **Statement (D): Mycoplasma cannot survive without O2.**
- Mycoplasma species are known to be anaerobic, meaning they can survive in environments without oxygen. They can thrive in anaerobic conditions, which makes this statement **incorrect**.

### Conclusion:
The correct statements are (A), (B), and (C). Therefore, the answer is that statements A, B, and C are correct.