The answer you are looking for would be C. "She asks her lab partner which base he thinks is hardest to study"
This is the correct option out of the other choices.
A. She uses a acid-base indicator to measure the pH of four different solutions
B. She mixes two solutions and measures their pH before and after
C. She asks her lab partner which base he thinks is the hardest to study
D. She measures the temperature of a solution before and after adding H2SO4
