-    Investment =Rs.(20 x 8 + 10) = Rs.170
  Receipt = Rs. (30 x 5 + 20 x 4)  = Rs.230.
  Gain% = (60/170 x 100)%  = 35.29% 
  =35.3%

Detailed Solution:
Definition of Profit:
Profit is the difference between the amount realized from the sale of goods or services and the cost incurred in producing them.

Calculation of Profit:
To calculate the profit made by the person in the given transaction, we need to determine the total cost and the total amount realized from the sale of cream and toned milk.

Total Cost:
The total cost incurred by the person in the given transaction can be calculated as follows:

Total Cost = Cost of 20 liters of Milk + Cost of churning
= 20 x 8 + 10
= Rs. 180

Total Amount Realized:
The total amount realized from the sale of cream and toned milk can be calculated as follows:

Total Amount Realized = Sale of 5 kg of Cream + Sale of 20 liters of Toned Milk
= 5 x 30 + 20 x 4
= Rs. 250

Profit:
Now, the profit made by the person in the given transaction can be calculated as follows:

Profit = Total Amount Realized - Total Cost
= 250 - 180
= Rs. 70

Profit Percentage:
The profit percentage made by the person in the given transaction can be calculated as follows:

Profit Percentage = (Profit / Total Cost) x 100
= (70 / 180) x 100
= 35.3 %

Hence, the correct answer is Option B (35.3%)

If you think the solution is wrong then please provide your own solution below in the comments section .