Option 1 states that all states have equal representation in the Rajya Sabha. This statement is incorrect as the Rajya Sabha follows a system of unequal representation, where states have representation based on their population.

Option 2 states that the consent of a state is not required for altering its boundaries. This statement is correct. According to Article 3 of the Indian Constitution, the Parliament has the power to alter the boundaries of states without the consent of the affected states.

Option 3 states that there is no dual citizenship in India. This statement is correct. The Indian Constitution does not recognize dual citizenship. A person can be a citizen of India only and not simultaneously hold citizenship of any other country.

So, the correct answer is option 2, which states that statements 2 and 3 only are correct.