The correct answer is option 3, which indicates that statements 2 and 3 are correct.

Let`s break down each statement:

1. No safeguard mechanism for developing country members: This statement is incorrect. The Nairobi Package did include a safeguard mechanism for developing country members. The safeguard mechanism allows developing countries to temporarily increase tariffs on specific products to protect domestic industries from sudden surges in imports.

2. Preferential rules of origin for least developed countries: This statement is correct. The Nairobi Package did include preferential rules of origin for least developed countries. These rules provide certain benefits to the least developed countries in relation to trade, such as easier access to markets and preferences in trade policies.

3. Public stockholding for food security purposes: This statement is correct. The Nairobi Package did include provisions for public stockholding for food security purposes. Public stockholding allows countries to maintain stocks of food grains for food security purposes without violating their WTO obligations.

In summary, option 3 is the correct answer as it states that statements 2 and 3 are correct.