Final answer:
The likely market response to rising material prices making it costly to produce regular cell phones is an increase in cell phone prices.
Step-by-step explanation:
When rising material prices make it costly to produce regular cell phones, the likely market response would be an increase in cell phone prices. As the cost of materials increases, it becomes more expensive for manufacturers to produce cell phones, which results in higher production costs. To compensate for these increased costs, manufacturers may raise the prices of cell phones to maintain profitability.