The chart shows the voltage of four electric currents.

A 2-column table with 2 rows titled Voltage of Currents. The first column labeled Current has entries W, X, Y, Z. The second column labeled Volts (volts) has entries 9.0, 1.5, 3.0, 4.5.
Which is best supported by the data in the chart?

Current W flows at a higher rate than Current Z.
Current Y flows at a lower rate than Current X.
Current X has a lower potential difference than Current Y.
Current Z has a greater potential difference than Current W.

Current X has a lower potential difference than Current Y.

Explanation:

The table is as follows:

Current Volts (V)

W     9.0

X      1.5

Y      3.0

Z      4.5

There are two quantities represented in the table:

1) Current: the current is the rate of flow of electric charge in a circuit. It is given by

where q is the amount of charge that passes a given point of a circuit in a time t. It is measured in Ampere (A).

2) Potential difference: the potential difference is the difference in electric potential between two points of a circuit. The potential difference is responsible for "pushing" the electrons through the circuit and producing a current. It is measured in Volts (V).

From the table, we see that

Current X has a lower potential difference (1.5 Volts) than Current Y (3.0 Volts)

So the correct choice is

Current X has a lower potential difference than Current Y.

the reason is because the moon has some form of gravity, and that gravity pulls the ocean tides.