Question

so far we know three things:
to clean these birds we need a substance that can dissolve in both oil and water
oil is nonpolar and dissolves in nonpolar substances
water is polar and dissolves in polar substances
what does this mean for the molecule we are looking for?
it must be polar
it must be nonpolar
it must be neutral
it must be an ion
it must have polar and nonpolar regions
none of the above
all of the above

Explanation:

Since the substance needs to dissolve in both oil (non - polar) and water (polar), it must have regions that can interact with both. A molecule with polar and non - polar regions (amphiphilic) can dissolve in both. Polar substances only dissolve in polar (so not good for oil), non - polar only in non - polar (not good for water), neutral may not have the right interactions, ions are charged and may not dissolve well in non - polar oil.

Answer:

It must have polar and nonpolar regions.