Select the incorrect option -

Options

A. Primary growth is the increase in girth of axis due to activity of Apical meristem
B. Secondary growth is the increase in girth due to activity of lateral meristem (vascular cambium & cork cambium)
C. Elongation of plant is the primary growth
D. b and c

Answer

To solve the question of selecting the incorrect option regarding plant growth, we will analyze each option provided:

1. **Understanding Primary Growth**:
- Primary growth refers to the increase in length of the plant, which occurs due to the activity of the apical meristem located at the tips of roots and shoots.
- This option states that primary growth increases the width of the axis, which is incorrect. Therefore, this option is indeed incorrect.

2. **Understanding Secondary Growth**:
- Secondary growth refers to the increase in thickness or girth of the plant, primarily due to the activity of lateral meristems such as the vascular cambium and cork cambium.
- The statement in this option is correct as it accurately describes secondary growth.

3. **Understanding Elongation of Plant**:
- The elongation of the plant is a characteristic of primary growth. This option correctly states that elongation is a result of primary growth.
- Therefore, this option is also correct.

**Conclusion**:
- After analyzing all the options, we find that option 1 is the incorrect statement regarding plant growth.

**Final Answer**: The incorrect option is option 1.