Answer: Option C.
The number of protons and neurons it's contain.
Explanation:
Mass number of an atom is also called atomic mass of an atom which is some what expressed in Dalton i.e 1/2. The mass number is the total number of protons and neutrons altogether called nucleons in an atomic nucleus.
Answer: The main properties of water are its polarity, cohesion, adhesion, surface tension, high specific heat, and evaporative cooling.
Water has the unique ability to dissolve many polar and ionic substances. This is important to all living things because, as water travels through the water cycle, it takes many valuable nutrients along with it! Water has high heat capacity.
The Objective of the experiment, the hypothesis, the variables Like Independent Variable, Dependent, Variable, Controlled Variable

Answer:
Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
Explanation:
Hope this helps.
Answer:
What is population?
A group of organisms of different species interacting with each other and the environment is called populatin.
Answer:
C. Prolactin
Prolactin is a
hormone that controls milk production together with oxytocin. The anterior lobe of the
pituitary gland secretes prolactin and the posterior lobe secretes oxytocin when
a baby suckles at the breast. The level of prolactin in the blood slowly
increases during pregnancy, and stimulates the growth and development of the
mammary tissue, in preparation for the production of milk after delivery.
Moreover, Prolactin
is in the highest level in about 30 minutes after the beginning of the feed,
which is most important for producing milk for the next feed.