Answer:
I think option B is right answer
Cold air usually pushes warm air because cold air has a HIGHER DENSITY
Parasitism bc the warbler's young are being displaced which means that the warblers are suffering harm through the loss of their young.
Valence shell
The number of electrons in the outermost shell of a particular atom determines its reactivity, or tendency to form chemical bonds with other atoms. This outermost shell is known as the valence shell, and the electrons found in it are called valence electrons.
Simple sugar dehydration–fragmentation products, such as derivatives of furans, pyrones, cyclopentenes, carbonyl compounds, or acids
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please brainliest :)