If two or more resistors are connected in series, they collectively behave as one resistor with an equivalent resistance that is: a. equal to the sum of the squares of the individual resistors.
b. equal to the sum of the individual resistors.
c. inversely equal to the sum of the inverses of the individual resistors
d. equal to the the sum of the currents through the resistors multiplied by sum of the voltages across the resistors.