Answer:
naturalistic observation
Explanation:
In naturalistic observation, researchers will gather data by directly observing the subjects in their natural habitat without making any intervention.
This is what Professor Ober is doing.
Professor Ober wants to collect a data about development of their physical skills among children. This means that the <u>children are his research subjects.</u>
To collect his data, professor Ober observed the children in the playground (which is the children's natural habitat). He also did not told the children to do anything , he just quietly observe and let the children do what they usually do. (not making any intervention)
The correct answer is known as "Concrete Operational Stage".
The Concrete Operational Stage of Cognitive Development is known as the third of <span>Piaget's research </span><span>of cognitive </span>improvement<span>. </span>this period<span> spans the time of </span>center early life<span> and is </span>characterized with the aid of<span> the </span>development<span> of logical </span>idea<span>. </span>whilst children<span> at this age </span>emerge as extra<span> logical </span>approximately<span> concrete and </span>unique matters<span>, they </span>nonetheless battle<span> with </span>abstract ideas<span>.</span>
due to decline in product