Consider the following statements about British constitutional reforms in India:

1. The Charter Act of 1833 centralized legislative powers in the hands of the Governor-General of India and abolished the East India Company’s commercial monopoly, except for trade with China and opium.

2. The Indian Councils Act of 1909 introduced separate electorates for Muslims, which allowed them to vote for Muslim representatives in provincial legislative councils and the Imperial Legislative Council.

3. The Government of India Act, 1919 introduced Dyarchy, which divided subjects into "transferred" and "reserved" categories in provincial administration, with Indians given limited control over transferred subjects.

4. The Government of India Act, 1935 abolished Dyarchy in provinces, introduced provincial autonomy, and proposed a federal structure, which included both British Indian provinces and princely states.

Which of the statements are correct?