Select the CORRECT statements from the following :
(P) In monocots , leaf base expands into sheath covering the stem partially or wholly
(Q) In all leguminous plants, the leaf base may become swollen , which is called the pulvinus
(R) The lamina or leaf blade bis green expanded part of the leaf with vein and veinlets
(S) veins provide rigidity to leaf blade

Options

A. P and Q only
B. R and S only
C. All except Q
D. All

Answer

To solve the question, we need to evaluate each statement (P, Q, R, S) regarding their correctness.

### Step 1: Evaluate Statement P
**Statement P:** In monocots, the leaf base expands into a sheath covering the stem partially or wholly.

- **Analysis:** This statement is correct. In monocotyledonous plants (monocots), the leaf base does indeed expand to form a sheath that can cover the stem either partially or completely.

### Step 2: Evaluate Statement Q
**Statement Q:** In all leguminous plants, the leaf base may become swollen, which is called the pulvinus.

- **Analysis:** This statement is partially correct. While many leguminous plants do have a swollen leaf base known as the pulvinus, it is not true for all leguminous plants. Therefore, this statement is incorrect.

### Step 3: Evaluate Statement R
**Statement R:** The lamina or leaf blade is the green expanded part of the leaf with veins and veinlets.

- **Analysis:** This statement is correct. The lamina (or leaf blade) is indeed the green, flat part of the leaf that contains veins and veinlets.

### Step 4: Evaluate Statement S
**Statement S:** Veins provide rigidity to the leaf blade.

- **Analysis:** This statement is also correct. The veins in the leaf help provide structural support and rigidity to the leaf blade.

### Conclusion
After evaluating all statements:
- **Correct Statements:** P, R, S
- **Incorrect Statement:** Q

### Final Answer
The correct statements are P, R, and S.

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