The answer is B because convection is the transfer of heat without two objects touching.
A chromosome is made of both one DNA molecule wound around small protein molecules whereas DNA is just one large molecule called deoxyribose nucleic acid.
C. protein. Nitrogen is a component of amino acids which are the building blocks of protein.
Soil is a mixture of broken rocks and minerals, living organisms, and decaying organic matter called humus. Humus is dark, soft and rich in nutrients. Soil also includes air and water. Organisms in the soil need air and water to survive.
