Question

during action potential, positively charged ------ ions move inside the cell. bromine chloride potassium sodium

Explanation:

During an action potential, sodium ($Na^+$) ions move into the cell. Sodium ions are positively - charged and their influx is a key step in the generation of the action potential. Bromine and chloride are negatively - charged anions and potassium ions move out of the cell during repolarization phase of action potential.

Answer:

sodium