Consider the following statements regarding Kautilya’s Arthshastra :

1. It places morality higher than political expediency.

2. It argues the case for a fully-centralised government for the empire.

3. It deals with problems of administration as well as laws of property and crime.

4. It refers to women spies being more efficient than men, so they should, in particular, be recruited as spies.

Which of the statements given above are correct?