Maybe some medical condition :)
Answer:
because when talking about sensitive topics like death, love, body processes, anything they might not want to speak of directly.
Explanation:
hope this helps :-)
The second one, and the last one
Answer: Our future does not exist, just like alien invasions do not exist either.
Explanation: We build our own future, in the present with plans, which will become true if we work hard. Alien invasions can only exist in our mind, just like future only exists in our minds at the present. Do not let your mind be "invaded" by "aliens", invade your mind yourself with amazing plans.
D, value conflict. Work is his opportunity cost because he values church more.
