Consider the following statement and select correct set for brown algae as well as red algae.
(i) Certain marine forms produce large amonts of hydrocolloids.
(ii) Used as food supplements by space travellers.
(iii) Organisms may have unicellular and multicellular plant body.
(iv) They have cellulose in cell wall and chlorophyll a pigment.

Options

A. (i) & (iv)
B. (ii) & (iii)
C. (i) & (iii)
D. (iii) & (iv)

Answer

To solve the question regarding the correct statements for brown algae and red algae, we will analyze each statement provided in the question step by step.

### Step 1: Analyze Statement (i)
**Statement:** Certain marine forms produce large amounts of hydrocolloids.

**Analysis:**
Both brown algae (Phaeophyceae) and red algae (Rhodophyceae) are known to produce hydrocolloids. Brown algae produce alginates, while red algae produce agar and carrageenan. Therefore, this statement is correct for both types of algae.

### Step 2: Analyze Statement (ii)
**Statement:** Used as food supplements by space travelers.

**Analysis:**
This statement is misleading. Space travelers typically use spirulina, which is a type of blue-green algae (cyanobacteria), not brown or red algae. Therefore, this statement is incorrect for both brown and red algae.

### Step 3: Analyze Statement (iii)
**Statement:** Organisms may have unicellular and multicellular plant body.

**Analysis:**
Both brown algae and red algae are predominantly multicellular. While there are some unicellular forms in algae, the main representatives of both brown and red algae are multicellular. Thus, this statement is also incorrect.

### Step 4: Analyze Statement (iv)
**Statement:** They have cellulose in cell wall and chlorophyll a pigment.

**Analysis:**
Both brown algae and red algae have cellulose in their cell walls. Brown algae contain chlorophyll a and chlorophyll c, while red algae contain chlorophyll a and phycobilins (like phycoerythrin). Therefore, this statement is correct as both types of algae contain chlorophyll a.

### Conclusion
Based on the analysis:
- Statement (i) is correct.
- Statement (ii) is incorrect.
- Statement (iii) is incorrect.
- Statement (iv) is correct.

Thus, the correct set for brown algae and red algae includes statements (i) and (iv).

### Final Answer
The correct options for the statements regarding brown algae and red algae are (i) and (iv).

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