The four limitations are
1.It's often impossible to repeat trials on the same subjects.
2-Subjects may report an inaccurate medical history.
3-It can be difficult to control all possible variables.
4-It's impossible to come up with testable scientific questions for human subjects.
Research involving human beings is ultimately necessary for improvements in human health and welfare. Any results about healthy physiology, illness causes, treatment effectiveness, learning, or behavior must be verified by carefully controlled investigations involving human participants. Sadly, not all human research have been valid and beneficial. It is possible to harm people in the name of research. The most well-known instances happened in Nazi Germany. Investigations conducted after the war found several crimes, including experiments in which participants were submerged in extremely cold water to determine how long it would take them to pass away from hypothermia.
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Hello there,
Your correct answer would be "<span>Increased surface area, Increased output".
I researched this up for you. I wanted to provide and good and fair answer.
Hope this help's.
~Jurgen</span>
Yes, that is true. However, a penis can temporarily enlarge from blood flow (an erection) or it can be surgically manipulated. Hope that helps!
The answer is the last choice, or ‘ GG and Gg’
