Explanation:

- Urbanisation is a product of industrialisation: As industries develop, people move to urban areas for better job opportunities and living standards. This is true.

- Diversity of occupations is a characteristic of urban life: Urban areas offer a variety of job opportunities beyond agriculture, reflecting this diversity. This statement is accurate.

- Rural urban migration continues to contribute a major part to the growth of urban population: Many people still move from rural areas to cities for better prospects, contributing significantly to urban growth. This is a correct observation.

- Owing to urbanization and industrialization the population is highly complex in cities: Urbanisation and industrialisation bring diverse cultures and people, adding to the complexity. This statement holds true.

- All statements are correct; they describe the characteristics and impacts of urbanisation and industrialisation accurately.

So, the correct option is:

- Option: 1, 2, 3 and 4