The four major categories of qualitative research designs are a. historical, ethnography, grounded theory, and exploratory. b. experimental, descriptive, exploratory, and ethnography. c. ethnography, phenomenology, experimental, and quasi-experimental. d. phenomenology, ethnography, grounded theory, and historical. 3.33 points

The correct answer is D. phenomenology, ethnography, grounded theory, and historical.

Explanation:

The four major categories of qualitative research designs are PHENOMENOLOGY, ETHNOGRAPHY, GROUNDED THEORY, AND HISTORICAL.

d. phenomenology, ethnography, grounded theory, and historical

Explanation:

There are four major types of qualitative research design that have been in use. These four include; the phenomenology (describing something existing integrally as a part of the world we live in), ethnography (a branch of anthropology that gives a scientific account of individual human societies), grounded theory ( allowing theory/theories to emerge from data collection and analysis), and case study/historical (Based on an occurrence or series of occurrences)

explanation:

allergens: overstimulate the nerve system

neurotics: attack nerve cells

mutagens: damage or otherwise alter dna sequence

generators: cause defects during growth and development  

carcinogens: cause unchecked cell growth

i hope you get the idea according to me these are the effects that happened.