One group dilutes the acetic acid to 50 mL in their titration beaker to fully cover the pH probe and another group dilutes it to 100 mL to fully cover the pH probe. how would that affect the number of milliliters of 0.10M NaOH needed to neutralize it (to reach the equivalence point, also known as the stoichiometric point)?

A) It will take twice as many milliliters of 0.10 M NaOH to neutralize the diluted acid solution.
B) It will take the same number of milliliters of 0.10 M NaOH to neutralize the diluted acid solution.
C) It will take half as many milliliters of 0.10 M NaOH to neutralize the diluted acid solution.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.