The answer is the difficulty of determining what is real. Typical modernists had a loss of meaning in the modern world, so there themes included the question of "What is real?" There was a search for meaning in a world without God, and a search for self with a critique of traditional values.
What do you mean by this question?
For indicating time, the best answer is C- During, because this word tells a reader when an action is taking place.
Again implies that something has been done before, and is being done again, but does not imply <em>when</em> it is being re-done.
Furthermore is a word with a similar meaning to "Also", so it is not connected to the idea of time.
Besides generally means "other than" which, again, has no connection to time.
