Answer:
The answer is B. Stratum Basale
<span>Air pollution is the presence of harmful substances in the earths atmosphere </span>
<h2>Operational </h2>
Explanation:
The operational definition is the description of a specific process, or set of validation tests, accessible to more persons than the definer (i.e., said to be publicly accessible), where it can be repeatedly measured or tested
Operational definitions are also used to define system states or (nonspecific) physical objects by the description of a specific process of preparation which can be repeated
For example in the given example experimenter is using the case of hitting a punching bag to measure the level of aggression in someone
I think it is stage 2
At stage two, the skin breaks open, wears away, or forms an ulcer, which is usually tender and painful. The sore expands into deeper layers of the skin. It may appear as a scrape, blister, or a shallow crater in the skin. At times this stage looks like a blister filled with clear liquid. Also at this stage some skin may be damaged beyond repair or may die.