Which of the following might explain the lack of "water worlds"—small planets made mostly of water or other hydrogen compounds—in our own solar system?
a) water worlds can form only on eccentric orbits.
b) there was not enough water in our solar system.
c) in our solar system, the solar wind did not clear out gas until relatively late.
d) small worlds in our solar system formed only close to the sun, where it was too hot for hydrogen compounds to condense.

Ibelieve the answer is b

Answer:   [a]:   "slate" .

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current