In a dry cell (battery), the electrolyte is a substance that enables the flow of electric current between the electrodes. The correct answer is option 'A', which states that ammonium chloride and zinc chloride are used as electrolytes in a dry cell battery.

Explanation:
Dry cell batteries are commonly used in various electronic devices such as flashlights, calculators, and remote controls. They are called "dry" cells because they do not contain free-flowing liquid electrolytes like wet cells or lead-acid batteries. Instead, dry cells use a paste or gel-like electrolyte.

Ammonium chloride and zinc chloride are commonly used as electrolytes in dry cell batteries. Let's understand why:

1. Ammonium chloride (NH4Cl):
Ammonium chloride is a white crystalline salt that dissolves in water to form ammonium ions (NH4+) and chloride ions (Cl-). In a dry cell battery, ammonium chloride is mixed with a gelling agent to form a paste. The ammonium ions act as the positive ions (cations) in the electrolyte, while the chloride ions act as the negative ions (anions).

2. Zinc chloride (ZnCl2):
Zinc chloride is a white crystalline solid that also dissolves in water to form zinc ions (Zn2+) and chloride ions (Cl-). It is mixed with ammonium chloride in the electrolyte paste of a dry cell battery. The zinc ions act as the positive ions (cations) in the electrolyte.

Working of a dry cell battery:
Inside a dry cell battery, there are two electrodes - a zinc metal casing that acts as the negative electrode (anode) and a carbon rod that acts as the positive electrode (cathode). These electrodes are surrounded by a paste of ammonium chloride and zinc chloride electrolyte.

When the battery is connected to a circuit, a chemical reaction takes place at the electrodes. The zinc metal at the anode oxidizes, releasing two electrons and forming zinc ions (Zn2+). These electrons flow through the circuit, creating an electric current.

At the cathode, the ammonium ions (NH4+) from the electrolyte combine with the electrons and decompose, forming ammonia (NH3) gas and hydrogen gas (H2). These gases escape into the air. The chloride ions (Cl-) from both the ammonium chloride and zinc chloride remain in the electrolyte, balancing the positive charge of the zinc ions.

In summary, the combination of ammonium chloride and zinc chloride as the electrolyte in a dry cell battery allows the flow of electric current between the electrodes, enabling the battery to power electronic devices.