Introduction:
Partition noise is a type of noise that arises due to the interaction between the electromagnetic waves propagating in the transmission medium and the physical structure of the medium itself. This noise is prevalent in certain transmission modes and not in others.

Fibre Transmission:
Fibre transmission is a mode of transmission that utilizes optical fibres to transmit the signal. In this mode, the electromagnetic waves are transmitted in the form of light through the optical fibres. However, due to the physical structure of the fibre, which consists of multiple layers of glass or plastic, the electromagnetic waves interact with the partitions between the layers, resulting in partition noise.

Coaxial Line and Waveguide:
Coaxial line and waveguide are other modes of transmission that are commonly used in communication systems. However, these modes do not introduce partition noise. In coaxial lines, the electromagnetic waves are transmitted between the inner and outer conductors, which are separated by a dielectric material. In waveguides, the electromagnetic waves are guided through a metallic structure that is designed to contain the waves within a specific frequency range.

Conclusion:
In conclusion, fibre transmission is the only mode of transmission that introduces partition noise due to the interaction between the electromagnetic waves and the physical structure of the fibre. Coaxial line and waveguide do not introduce partition noise as they do not have such physical structures that could cause such interaction.