Studying the same group of individuals from age 2 to age 40 is an example of which of the following research methods?
a. cross-sectional
b. longitudinal
c. archival
d. none of the above

a. Cross sectional

Explanation:

Longitudinal research is a method in with data is recollected repeatedly over a period of time from the same subjects. Archival method is gathering information from archival records. Cross-sectional studies analyze data from a population at a specific period of time, this population can be integrated by people with different characteristics (in this case, age) but with another characteristics in common, for example, ethnicity, gender, etc)

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hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

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