Philomel
v=6/3=2v .
oubaas
V(1) = V*1/(1+1+1) = 6*1/3 = 2 Volts
Mr. Smartypants
You could use Ohm's law, use total resistance and voltage to figure the current, then figure that current against 1 ohm.
But you can also use common sense. If there are three 1-ohm loads in series, the voltage is equally distributed between them. Each resistor has 2 volts across it. So the answer is D.