What happens to all branches of a parallel circuit if one branch is changed?

In a parallel circuit, each branch operates independently of the others. This means that if one branch is changed—whether by adding, removing, or altering a component—the electrical characteristics of that particular branch will change, impacting the overall behavior of the circuit. However, the specific details about how this affects the current and voltage distribution across the remaining branches depend on the change made.

When a branch is changed, it can impact the total equivalent resistance of the circuit, which in turn affects the total current flowing through the circuit. Since current in parallel circuits is distributed among the branches, a modification in one branch may alter the current flowing through the remaining branches. Therefore, while individual branch currents will change due to the new conditions, the voltage across each branch will remain constant and equal to the supply voltage across the parallel network.

The only way all branches would simultaneously change in a parallel circuit context is if something affects the overall voltage supply or the characteristics of all branches simultaneously—something that isn't typical in standard configurations. Hence, assuming a general scenario in response to a change in one branch leading to alterations in all branches collectively aligns with the answer provided.