What does manipulated variable mean?

Why would a drug that damages capsids treat a viral infection? a. capsids prevent the lytic cycle from beginning. b. transduction requires a capsid. c. viruses use capsids to increase genetic variation. d. capsids provide protection for viruses.

For their summer holiday, jane and her family are visiting places surrounding the mediterranean sea. which type of biome is jane and her family visiting? a. rainforest b. shrubland c. tundra d. coniferous forest

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis