Potable water delivery systems are characterized by
a. high infrastructure costs
b. aqueducts
c. glass bottles
d. rivers

It's not rivers: some rivers are full of pollutants, and therefore the water there is not safe to drink.

It's also not glass bottles - as only a small fraction of potable water is delivered in glass bottles.

It could be aqueducts, but in the modern times it's rather underwater pipes

So the best answer is A!

Hamlet's fourth soliloquy is probably his most famous one - "to be or not to be."it is rather different from his previous soliloquies because now he is contemplating something that didn't come up before - suicide. he is thinking whether it is worth it to fight to find his father's murderer when in the end all of them are going to die, so why not die sooner than later. he is contemplating if he should go on fighting or just kill himself and end it all, which is why this soliloquy in particular is rather depressing, hesitant, and gives a deeper insight into hamlet's madness.