Final answer:
Anne Frank died of typhus, a disease exacerbated by the harsh conditions of the Bergen-Belsen concentration camp in 1945.
Step-by-step explanation:
Anne Frank's cause of death was typhus, which is an infectious disease spread by lice.
In the context of World War II, the conditions in concentration camps like Bergen-Belsen, where Anne and her sister Margot were transferred, were extremely poor with overcrowding, lack of hygiene, and minimal food which led to the outbreak of diseases such as typhus.
Anne Frank and her sister succumbed to typhus in February or March of 1945, just a few weeks before British troops liberated the camp in April 1945.