A tapeworm attaches to the wall of its host’s intestine and starts to absorb the host’s nutrients. Eventually this can cause great harm to the host as the host loses many important nutrients. Which type of infectious agent is a tapeworm?

a virus
a bacterium
a fungus
a parasite

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)