The only way (as far as I know) to be sure it is from a virus is if it is RNA (so contains U). This gives iii and iv, but as iv also contains T and only a small amount of U it is probably a mistake. This leaves only iii as the answer. I hope that helps
Did anyone take any courses to prepare for the British Biology Olympiad (BBO)? I am considering taking the introductory course to prepare for BBO 2025 but cannot find any reviews. How else can I prepare for BBO?
Hi - I don't own these, just found those mark schemes online after a lot of digging, for some friends who were sitting the BBO. Here's a Google drive link with the pdfs:
On Biolympiads, there are past paper review sessions and I signed up for BBO past paper review. We went over the suggested answers, but there are no official answer keys released.