Choose the correct statement

Options

A. (a) AlDS day is celebrated on 1 December
B. (b) Influenza virus has ssRNA
C. (c) ssDNA of `phi xx 174` is called plus strand
D. (d) All of the above.

Answer

**Step-by-Step Solution:**

1. **Analyze Statement A**: The statement claims that AIDS Day is celebrated on December 1st. This is a well-known fact as World AIDS Day is indeed observed on December 1st every year to raise awareness about HIV/AIDS. Therefore, Statement A is true.

2. **Analyze Statement B**: The statement mentions that the influenza virus has single-stranded RNA. This is accurate; the influenza virus is classified as an RNA virus and specifically has a segmented single-stranded RNA genome. Thus, Statement B is also true.

3. **Analyze Statement C**: The statement refers to the single-stranded DNA of the 5174 virus being called a plus strand. This is correct as the single-stranded DNA can be referred to as the positive or sense strand, which corresponds to the RNA transcript that is produced. Hence, Statement C is true as well.

4. **Conclusion**: Since all three statements (A, B, and C) are true, the correct answer is option D, which states that all of the above statements are correct.

**Final Answer**: D) All of the above.

---