Electrons flow from the negative terimal of a
battery to the positive terminal. Conventional flow
assumes that current flows
A out of the negative terminal, through the circuit
and into the positive terminal of the battery.
B out of the positive terminal, through the circuit!
and into the negative terminal of the battery.
C out of the positive terminal, goes into the first
resistor, changes direction, and goes back into
the positive terminal of the battery.
D. out of the negative terminal, goes into the first
resistor, changes direction, and goes back into
the negative terminal of the battery.

The electrons flow from negative terminal of a battery to the positive terminal because as the charge of electron is negative, it will get repelled by the negative terminal of the battery

Conventional flow actually assumes that the current flows out of the positive terminal, through the circuit and into the negative terminal of the battery

It actually says that direction of flow of current is in opposite direction to the direction of flow of electrons

The direction of current will not change even a resistor is placed in the circuit and it generates a potential difference across the resistor

But the current tries to move in such a way in which there will be less resistance to the flow