discreet- careful and circumspect in one's speech or actions, especially in order to avoid causing offense or to gain an advantage.
"we made some discreet inquiries"
<span>B)
Postgraduate programs in a wide variety of majors
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A because external means what is happening outside of you while all the others are internal which is what happens inside us emotionally.
Answer:
It is contrasting what produces the pulling power of a whirlpool and a black hole.
Explanation: I just did the assignment in edge:)