Which system in the body acts as a transportation system?

When a person undergoes root canal treatment or another endodontic treatment: [select all that apply] a.) the inside of the tooth is carefully cleaned and disinfected. b.) air is forced into the canal to stop bleeding. c.) the inflamed/infected pulp is removed. d.) the inside of the tooth is filled and sealed with a rubber-like material called gutta-percha

Based on the chart, what are the three most effective methods to protect against pregnancy?

How can the stress response be used in a way. for example to build resilience.