What change occurs in a circuit powered by a battery when a parallel branch is added?

When a parallel branch is added to a circuit powered by a battery, the total current supplied by the battery increases. This is because in a parallel configuration, each branch provides an alternative path for current to flow. According to Kirchhoff's junction rule, the total current in a circuit is equal to the sum of the currents flowing through each branch.

As new branches are added, the overall resistance of the circuit decreases, which leads to an increase in total current drawn from the battery, assuming the voltage supplied by the battery remains constant. This phenomenon can be understood using Ohm's law, where current (I) is equal to voltage (V) divided by resistance (R). With a decrease in total resistance, the total current increases proportionately for the same applied voltage.

In contrast, adding a parallel branch does not decrease the voltage provided by the battery, as the voltage across each parallel branch remains the same. Additionally, the current through existing branches does not necessarily decrease; rather, it is distributed among all branches. Thus, the action of adding branches leads to an increase in total current from the battery, confirming that the correct answer is the increase in current.