Which of the following statement is incorrect?

Options

A. In monocotyledons, the leaf base expands into a sheath covering the stem partially or wholly
B. In some grasses, the leaf base may become swollen , which is called the pulvinus
C. The leaf blade is the green expanded part of the leaf with verins and veinlets
D. Leaves originate from shoot apical meristems and are arranged in an acropetal order.

Answer

To determine which statement is incorrect, we will analyze each option provided in the question step by step.

### Step 1: Analyze the first statement
**Statement:** In monocotyledons, the leaf base expands into the sheath covering the stem partially or wholly.

- **Explanation:** This statement is true. In monocotyledons (like grasses), the leaf base indeed expands to form a sheath that can cover the stem either partially or completely.

### Step 2: Analyze the second statement
**Statement:** In leguminous plants, the leaf base is swollen which is called pulbinous.

- **Explanation:** This statement is incorrect. The term "pulvinus" refers to a swollen leaf base, but it is typically associated with certain plants, including some legumes, not all. However, the statement incorrectly generalizes this feature to all leguminous plants, which is misleading.

### Step 3: Analyze the third statement
**Statement:** The leaf blade is the green, expanded part of the leaf with veins and veinlets. Leaves originate from the shoot apical meristem and are arranged in the acropetal order.

- **Explanation:** This statement is correct. The leaf blade is indeed the green part of the leaf that contains veins and veinlets. Additionally, leaves do originate from the shoot apical meristem and are arranged in an acropetal order (from the base of the stem upwards).

### Conclusion
Based on the analysis, the incorrect statement is the second one regarding leguminous plants.

### Final Answer
**The incorrect statement is:** In leguminous plants, the leaf base is swollen which is called pulbinous.

---