RNA is

Options

A. single helix strand
B. double helix strand
C. right hand twisted double helix strand
D. triple helix strand

Explanation

To answer the question "RNA is", we need to analyze the structure of RNA (ribonucleic acid) and compare it with the given options. Here’s a step-by-step solution:

### Step 1: Understanding RNA Structure
RNA is a type of nucleic acid that plays a crucial role in various biological processes. Unlike DNA, which is typically double-stranded, RNA is usually single-stranded.

**Hint:** Remember that RNA is primarily involved in protein synthesis and gene expression, which is facilitated by its single-stranded structure.

### Step 2: Identifying the Components of RNA
RNA is composed of nucleotides, which consist of a ribose sugar, a phosphate group, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), and uracil (U).

**Hint:** Focus on the types of bases present in RNA to distinguish it from DNA, which contains thymine (T) instead of uracil.

### Step 3: Analyzing the Given Options
Now, let's evaluate the options provided:
- **Single helix strand**: This suggests a single-stranded structure, which aligns with the known structure of RNA.
- **Double helix strand**: This is characteristic of DNA, not RNA.
- **Right hand twisted double helix strand**: Again, this describes DNA, not RNA.
- **Triple helix strand**: This is not a common structure for RNA.

**Hint:** Recall that the term "helix" typically refers to the spiral structure, and in the case of RNA, it is predominantly single-stranded.

### Step 4: Conclusion
Based on the analysis, the correct answer is that RNA is a **single helix strand**.

**Final Answer:** RNA is a single helix strand.