### Step-by-Step Solution:
1. **Understanding Myriapods**:
- Myriapods are a subphylum of the phylum Arthropoda. They are characterized by having a large number of legs and are primarily terrestrial organisms. Common examples include millipedes and centipedes.
2. **Key Characteristics of Myriapods**:
- Myriapods have a chitinous exoskeleton, which is a common feature among arthropods. The exoskeleton provides structural support.
- They possess a ventral nerve cord, which is typical for invertebrates, including arthropods.
- Myriapods have a segmented body, typically consisting of 90 to 100 segments in the trunk.
- They have one pair of antennae on their head.
3. **Analyzing the Options**:
- **Option 1**: Chitinous exoskeleton, ventral nerve cord, 3 pairs of antennae.
- Incorrect because myriapods have only 1 pair of antennae.
- **Option 2**: Chitinous exoskeleton, ventral nerve cord, many body segments, 1 pair of antennae.
- Correct because it accurately describes myriapods.
- **Option 3**: Soft body, ventral nerve cord, many body segments, 2 pairs of antennae.
- Incorrect because myriapods have a chitinous exoskeleton and only 1 pair of antennae.
- **Option 4**: Chitinous exoskeleton, dorsal nerve cord, 3 body segments, 1 pair of antennae.
- Incorrect because myriapods have a ventral nerve cord, and they do not have only 3 body segments.
4. **Conclusion**:
- The correct answer is **Option 2**: Chitinous exoskeleton, ventral nerve cord, many body segments, and 1 pair of antennae.
