Answer:
a. But to some of us a day comes when we begin to grow weary of things.
Step-by-step explanation:
The phrase "But to some of us a day comes when we begin to grow weary of things", refers to a situation in which we tolerate for certain reasons, which allow us not to think that this situation is exhaustive or harmful to us, however over time, our opinion about this situation may change and with that we will begin to not tolerate it, we literally get tired and abandon the situation.
For this reason, we can say that this phrase represents a statement that shows that people's ideas about things change over time.