Melissa heated a few blue crystals in a test tube. after a few minutes, she observed that the crystals had turned white and a film of water had formed on the inside of the test tube.  before  melissa conducted this experiment, she most likely  developed a theory. developed a hypothesis. developed a bias. developed a scientific law.

It should be d if not then c

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

When seismic waves hit a fault, the waves are reflected off the fault. seismograph can detect these reflected seismic waves. geologists then use these data to map the fault's length and depth