Exercise 1: Read the following passage about mental health and mark the letter A, B, C, or D on your answer sheet to indicate the option that best fits each of the numbered blanks

The decline in teen mental health dates from 2010-12, ___(1)___, so is it that simple? For a thoughtful, expert looks at how far correlation is likely to mean causation, I read psychologist Jacqueline Nesi, ___(2)___. Nesi does believe social media is likely to be a significant factor, but points out as how varied social media use is (it’s the place you find support and connection, too, after all) and how multifaceted any explanation of this kind of large-scale crisis needs to be.
___(3)___, this kind of alarming news tends to prompt people to air their pet assumptions and I suppose mine is that online is basically the air we, including teenagers, breathe now. It’s ___(4)___, but what’s the alternative? All we can do is ___(5)___.
(Adapted from Think)