Cathode is
(A) Positively charged electrode.
(B) Negatively charged electrode.
(C) A positively charged ion formed in the electrolyte.
(D) A negatively charged ion formed in the electrolyte.

Hint: The cathode is a negatively charged electrode that attracts the cation or positively charged towards it. The anode is a positively charged electrode that attracts the negative charge or anion towards it. An electrolyte dissociates into its ions in solution. Ions conduct electricity.

Complete step-by-step answer:
The cathode is a negatively charged electrode.
Conventional current flows from cathode to anode outside of the cell or device regardless of the cell or device type and operating mode. Positively charged ions flow towards the cathode and negatively charged ions towards the anode.
We know that electrolyte dissociates into the solution to formits correspondinginons. Electrolytes are the solutions that produce ions to conduct electricity .option (C) and (D) cannot be true.
Therefore, the cathode is a negatively charged electrode.
Hence, option (B) is the correct option.

Additional information:
Cathodes are divided into two types:
1. Hot cathode
2. Cold cathode

Hot cathode: cathode that is heated by a filament to produce electrons by thermionic emission. hot cathodes are widely used in vacuum tubes, radio transmitters, microwave ovens, televisions and computer monitors, etc.

Cold cathode: cathode that is not heated by a filament. Cold cathode emits electrons by field emission electrons and in gas-filled tubes by secondary emission. These are called photo-cathodes and are used in phototubes.
The electrolyte is a substance that dissolves in a polar solvent and separates into cations and anions to produce an electrically conducting solution.

Note:
1. Conventional current flow with electrons moving in the opposite direction.
2. Cathode polarity concerning anode can be positive or negative depending on which condition the device is being operated.
3. In a P-N junction diode, the cathode is an n-type layer with a high density of free electrons due to doping.