Refer to figure. 
Two different types of ammeters are commonly used in aircraft electrical systems. The left-zero ammeter and the centre-zero ammeter, each with a distinct function:

• The indicates the generator load, showing how much current the generator is supplying to the electrical system
• The centre-zero ammeter indicates battery current

When the generator is running:

• The generator provides power and the left-zero ammeter displays a load value
• The battery is usually being recharged, so the centre-zero ammeter shows a positive value

Indicate the flow of current into and out of the battery → CORRECT. The centre-zero ammeter is positioned in the circuit between the battery and the bus in a configuration that allows it to measure bidirectional current: positive deflection = current flowing INTO the battery (charging) from the alternator, negative deflection = current flowing OUT of the battery (discharging) to supply the load. This bidirectional indication is the defining purpose of the centre-zero ammeter.

Indicate the flow of current from the alternator → INCORRECT. Current from the alternator is indicated by a LOADMETER o rleft-zero ammeter placed in the alternator output circuit. This type of ammeter shows alternator output in one direction only (positive) and does not show battery current flow.

Indicate the flow of current from the battery to the alternator → INCORRECT. Current does not flow from the battery TO the alternator during normal operation. Current flows from the alternator to the bus and to the battery for charging. 

Indicate the charged condition of the battery → INCORRECT. The state of charge of a battery is measured by voltage (using a voltmeter) or by hydrometer testing of electrolyte specific gravity. A centre-zero ammeter shows the instantaneous current flow direction and magnitude, not the battery state of charge. A fully discharged battery with the alternator charging it would show positive deflection, not a state of charge reading.