1 - sentence
2 - copy and paste
3 - make spelling error
Explanation : In order to write a research paper, the objectives of writing it should be very clear. We should not write irrelevant sentences that don not relate with the aim of the paper. While writing the paper in our own words, we should ensure not to copy and paste from other journals and keep the grammar right. The sentences should be well phrased and we should get our paper checked by someone for the purpose of proofreading.
For this answer I would go with D. Retinalogic. It is not a vitamin.
Answer:
A. Cohort study
Explanation:
It is basically a cohort study because in this we can evaluate the incident rate at a particular time for a particular disease. .
AIDS which results from HIV infections, results from the inability to fight off infections not the viruses direct attack on the immune system. This means other diseases as small as an Upper Respiratory Tract infection (a cold) or the flu, can hit much harder and are more lethal.
