Answer:
A unicellular organism is formed by a single cell. ... The circulation in unicellular organisms is carried out by the movement of the cytoplasm of the cell called cyclosis.
B) honey
A shirt is a solid, and helium is a gas at room temperature. A nebula is... not an object.
I would go with A, they inherited the wings even though they don't need them today, since evolution has changed the Ostrich in some way.
A)Demographic; because the census studies things such as births,death, and even disease which show changes in human population