1. Condition for osmosis and reverse osmosis

For two sugar solutions separated by a semipermeable membrane (SPM):

• Solvent naturally flows from lower concentration to higher concentration.
• The osmotic pressure difference is $\pi = (c_1-c_2)RT$ with $c_1>c_2$.

To cause reverse osmosis, we must apply an external pressure on the more concentrated side greater than the osmotic pressure difference: $p_1 > \pi$ where chamber 1 contains concentration $c_1$.

So reverse osmosis requires:

• a semipermeable membrane
• pressure applied on chamber 1 such that $p_1>\pi$

2. Check the membranes given

Semipermeable membranes for osmosis include:

• Cellophane
• Parchment paper

A porous partition is not semipermeable, so it cannot produce proper osmotic/reverse osmotic behavior.

3. Evaluate each statement

Statement A

Membrane: Cellophane, and $p_1>\pi$

• Cellophane is semipermeable.
• Pressure is applied on concentrated side and exceeds osmotic pressure.

So A is correct.

Statement B

Membrane: Porous, and $p_2>\pi$

• Porous membrane is not semipermeable.
• Also pressure is applied on chamber 2, the dilute side, which is not the condition for reverse osmosis here.

So B is incorrect.

Statement C

Membrane: Parchment paper, and $p_1>\pi$

• Parchment paper is semipermeable.
• Pressure is applied on concentrated side and exceeds osmotic pressure.

So C is correct.

Statement D

Membrane: Cellophane, and $p_2>\pi$

• Cellophane is semipermeable, but pressure is applied on chamber 2 (dilute side).
• Reverse osmosis requires pressure on the concentrated solution side.

So D is incorrect.

4. Select the correct option

Correct statements are A and C only.

Therefore, the correct option is: $\boxed{\text{A}}$

5. Comparison with stored answer

Stored correct answer = A

Our derived answer = A

They match.