Step 1: Recall the formulas.
\[
\text{Profit} = (100 - x)\% \text{ of Sales Revenue}
\]
\[
\text{Profit Rate} = \frac{\text{Profit}}{\text{Sales Quantity}} = \frac{(100-x)}{100} \times \text{Price}
\]
Thus,
\[
\text{Profit Rate} = \frac{(100-x)}{100} \times \text{Price (Rs./bag)}.
\]
Step 2: Compute profit rates for each quarter.
Oct -- Dec 2008:
For Paharpur: \(x = 92.11\), Price = 352
Profit Rate = \(\dfrac{(100 - 92.11)}{100} \times 352 = \dfrac{7.89}{100} \times 352 \approx 27.78\)
For Bahsin: \(x = 94.21\), Price = 438
Profit Rate = \(\dfrac{(100 - 94.21)}{100} \times 438 = \dfrac{5.79}{100} \times 438 \approx 25.36\)
Jan -- Mar 2009:
For Paharpur: \(x = 87.56\), Price = 304
Profit Rate = \(\dfrac{12.44}{100} \times 304 \approx 37.82\)
For Bahsin: \(x = 91.34\), Price = 440
Profit Rate = \(\dfrac{8.66}{100} \times 440 \approx 38.10\)
Apr -- Jun 2009:
For Paharpur: \(x = 91.03\), Price = 340
Profit Rate = \(\dfrac{8.97}{100} \times 340 \approx 30.50\)
For Bahsin: \(x = 89.96\), Price = 430
Profit Rate = \(\dfrac{10.04}{100} \times 430 \approx 43.17\)
Jul -- Sep 2009:
For Paharpur: \(x = 90.42\), Price = 322
Profit Rate = \(\dfrac{9.58}{100} \times 322 \approx 30.85\)
For Bahsin: \(x = 90.38\), Price = 434
Profit Rate = \(\dfrac{9.62}{100} \times 434 \approx 41.75\)
Step 3: Compare profit rates.
- Oct -- Dec 2008: Paharpur (27.78) > Bahsin (25.36)
- Jan -- Mar 2009: Paharpur (37.82) < Bahsin (38.10)
- Apr -- Jun 2009: Paharpur (30.50) < Bahsin (43.17)
- Jul -- Sep 2009: Paharpur (30.85) < Bahsin (41.75)
Thus, only in Oct -- Dec 2008, Paharpur’s profit rate is higher than Bahsin’s.
\[
\boxed{\text{Oct -- Dec 2008 only (Option C)}}
\]