Hormones are
a. produced only in response to environmental stress
b. chemical signals between cells, transported in blood or hemolymph
c. signals that must interact with dna in order to be effective
d. are all under the control of the pituitary gland
e. always proteins

The correct is B Hormones are chemical signals between cells transported in blood or hemolymph.

Explanation:

Hormones are called chemical messenger of the cell because they transmit chemical information from one cell to the target  cell and regulating the functioning of that target cell by activating specific proteins related to the functioning of that target cell.

          Hormone is secreted from its source gland such as Pituitarygland, thyroid gland,adrenal gland.After being secreted hormones are transported via the blood stream to the target cell and binds to receptor of that target cell thus allowing the target cell to exert its biological function.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.