The number of people is five and the plan is for each of them to have two pieces of chicken.
For option A:
Total cost = 10*3 = $30
Number of pieces = 10
For option B:
Total cost = 5*5 = $25
Number of pieces = 10
For option C:
Total cost = $20
Number of pieces = 12
For option D:
Total cost = $35
Number of pieces = 20
From the above, the best option to choose is option C.
This is because it has the least cost and the number of pieces is more than the needed.