Explain the relationship between an infectious disease and a contagious disease.

Infectious diseases are caused by microscopic germs (such as bacteria or viruses) that get into the body and cause problems. Some — but not all — infectious diseasesspread directly from one person to another. ... Contagious diseases (such as the flu, colds, or strep throat) spread from person to person in several ways.

Infectious diseases are usually caused by bacteria, viruses, fungi, or parasties and transmitted through microorganisms in the air or water.

 And contagious diseases are transmittable by contact from one person to another and/or  if a person touches an infected area. 

The correct answer is option A) "the same number of cells in both".

Explanation:

The volume of nutrient broth in two different cell cultures is not a variable that would affect the number of cells that are produced. The only way that this could be a factor would be if the cell number is high enough that the nutrients could be depleted. However, in this case where 100 cells with a generation time of 20 minutes are inoculated and the incubation time was of only 4 hours, the volume of nutrient broth is not a factor that would affect them.