An example of a communicable disease is:
a. cancer
b. chronic respiratory disease
c. diabetes
d. giardiasis

The correct answer is option D, Giardiasis

Giardiasis is a communicable disease that is spread by the parasite Giardia. Giradiasis is a form of diarrhea and the causative parasite spread through water, soil and food which is contaminated with feces of infected humans and animals. This parasite is resistant to even chlorine disinfection as the outer shell protect it for a longer period of time.

this age may represent the age of the earth's accretion, of core formation, or of the material from which the earth formed. this dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.

the two answers are a, the population of birds with large beaks will increase on the island, and c, the trait for large beaks will be passed on to future generations through natural selection. the reason for that is because if the birds that have beaks developed for eating small seeds lose all of their food, they will go hungry and eventually starve because they physically cannot eat the large seeds, therefore making the population of large beaked birds higher. also, if the trait of large beaks are dominant on the island over small beaks, then over time the large beaked birds will reproduce more and more, while the smaller beaked birds will reproduce less and less because they can't survive with the food provided. that leads to the trait of small beaks disappearing and the trait of large beaks taking over the island.