The answer would be D. The definition of a homologous structure is an organ or body part that appears in different animals and is similar in structure and location, but doesn't necessarily share the same purpose. The birds and rabbits have similar bones in their forelimbs, but one uses them to run and other uses them to fly.
DNA is located in the nucleus of the cell.
Mesoderm
Mesoderm is the primary germ layer that is responsible for producing both blood and phagocytic brain glial cells.
The mesoderm is the middle of the three germ layers that appears in the third week of embryonic development. The mesoderm is responsible for the formation of various body structures such as epithelia of blood vessels, blood, muscle, bone, phagocytic brain glial cells, lymphatic vessels, adrenal cortex, notochord, and bone marrow.
Answer:
B. Hardness
Explanation:
Physical properties of a substance is defined as the properties which can be observed or measured without changing the composition of matter.
Physical properties include odor, appearance, color, texture, boiling point, melting point and many others.
Hardness is a physical property of a substance as it describes the resistance of substance to deformation and can be observed by simple touch or without changing the composition of matter.
While reactivity, toxicity and flammability are chemical properties of substances that change one type of matter into another type.
Hence, the correct option is B.