What is one trait that could be used to separate these albatrosses into two groups of two birds each?

The correct answer to this open question is the following.

You did not attach the options for this question. However, we can answer the following.

Although there are no pictures of the Albatross, we can say that one trait that could be used to separate these albatrosses into two groups of two birds each is "a large group of solid black feathers vs. black and grey patterned feathers."

If someone ask you what are the birds with larger wings, you probably would answer "the Bald Eagle," Or any other kind of eagle. Maybe the Southamerican Condor. And those answers are incorrect. The correct the Albatross.

This is a carnivore bird which wingspan varies from 6.5 to 11 to 11 feet, Its average weight is 22 pounds. These impressive birds can use their long wings to fly over the seas for miles and miles, without taking a rest.

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

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