Final answer:
At a price of $1.70, Michael buys 3 muffins and Rose buys 7 muffins. The market demand for these individuals at a price of $1.70 is 10 muffins.
Step-by-step explanation:
In this scenario, Michael buys 3 muffins and Rose buys 7 muffins at a price of $1.70. The market demand for these two individuals at a price of $1.70 is the total number of muffins they purchased together, which is 3 + 7 = 10 muffins. Therefore, the correct answer is C. 10 muffins.