They can be described as possibly letting group members make decisions!
Human nature is the general psychological characteristics, feeling and behavioural traits of humans.
I think the railroad helped transportation in America because it provided a faster way to ship, sell, or send merchandise to farther places compared to horses and wagons that took days' worth of time to move the merchandise.
Answer: b). matched-samples design
Explanation:
Matched-samples design is the design in which matching mechanism in used samples. Participants share matched samples every characteristic expect for the trait that is being researched or experimented.
According to the question, matched pair of brother and sisters are involved in research for describing positivity rate in family in childhood.Thus, they have matched characteristics for finding positivity rate.
Other options are incorrect because repeated measure and both the measures together are not depicted through design in case.Thus, the correct option is option(b).
