All of the following are reasons why researchers use machines to record behaviors except a. human eye cannot record behavior that happens rapidlyb. humans cannot record and observe simultaneouslyc. machines can be disguised easilyd. design may require more than one person to be observed simultaneouslye. trained human observers are expensive

C. machines can be disguised easily

Explanation:

Observation is one of the important method used in the field of research in psychology. The results out of the observations help in evaluating the outcome and the result. Machines are used in the researches which helps to record the process and bring out certain conclusions out of them. Also, it helps in further researches equivalent to it. The data is recorded and is stored for any further assessment related to it.

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