Choose the correct statements among the following:
I. Bird flu is a fungal disease affecting poultry.
II. Propolis is bee glue used to seal the cracks in the honeycomb.
III. The world's livestock population in India and China together is more than 70%, but their contribution to world's farm produce is 25%.
IV. Inactivated whole agent vaccine acts against typhoid.
Which combination of statements is correct?