The researchers were following the ethical guideline that mandates <u>knowledge of results</u>.
<u>Explanation</u>:
Alcohol obstructs the storage ability of the brain. Alcohol influences information transfer from short-term memory to long-term storage. Hippocampus is a part of the brain which is mainly affected due to heavy drinking of alcohol. Hippocampus shrinks and reduces the size of brain cells.
Excessive drinking destroys brain tissue and can lead to several types of memory loss. Alcohol has immense effects on teens comparing to adults. Consumption of alcohol may lead to memory loss in teens.
Deforestation of part of the amazon rain forest was not a result of building the massive road system across Brazil. The correct option among all the options that are given in the question is the last option or option "D". I hope this is the answer you were looking for and hope that it helps you.
The correct answer would be D=4