Final answer:
If the resistance is increased and the voltage remains constant, according to Ohm's law, the current decreases. The answer to the student's question is option b) The current decreases.
Step-by-step explanation:
When considering the initial equation IR = I1R1, the implication is that current (I) is held constant while dealing with resistor values (R). However, Ohm's law, which states I = V/R (where I is current, V is voltage, and R is resistance), indicates that the current is inversely proportional to the resistance. Therefore, if the resistance (R) is increased and the voltage is held constant, the current (I) will decrease.
So, for the original question where it is mentioned that 'I is constant', if this condition needs to be maintained, an increase in R implies that the voltage must also increase to keep I constant. In a practical scenario where voltage is kept constant, as resistance increases, the current must decrease. Thus, the correct answer to the student's question would be:
b) The current decreases.