Answer: D)Psychological Effects of Nuclear Weapons
Step-by-step explanation:
Research that requires formal writing are those that need information that is controlled and objective, Such a research cannot be based on personal opinion as it would need to be peer-reviewed which means that there must be evidence to back it up and it must be in a strict format as well so that it is standardized enough to be reviewed.
The best option is therefore the last one which is about the psychological effects of nuclear weapons. This would requires evidence that is controlled and objective and based on actual fact. This is unlike the other options that require a lot of personal opinions and are therefore subjective.