Bio bored me to death. I dropped it at the end of yr 11. I only picked it so I could make up my units cause there wasn't much to pick in that line
But plus I love my History's
I'am doing Three: Ancient, Modern and Extension its a shitload of essays but I really Love Modern. I only picked Ancient cause I swapped from Business (it bored me too). Now I REALLY enjoy Anicent almost as much as Modern.
So in answer to your question choose Modern History. Also ask the Modern History teacher what topics they will be doing btw. We did the Romanov's Jack The Ripper (That was cool cause we had to solve it) and JFK (it was cool to another one we had to solve
Now We do WW1, Hitler/Germany and Conflict in the Pacific. Its really a good course if you get the right topics