Q. The Wuhan Institute of Virology is said to be the only laboratory in China capable of working with deadly viruses. Is it possible that the coronavirus contagion originated from there? If not, give your explanation for why not.
Let’s break down your question shall we:
You state “WIV is said it is the only laboratory in China ….” Ok, so, who said this? Put a body against the claim and then ask that body to provide evidence of the claim … otherwise, ‘is said to be’ is at best hearsay (or in this current environment rumor mongering)
Is it possible that the coronavirus contagion originated from there? Go back to point 1. But again, lets look at your word choice anyway. Now, possible is a very broad word, for example it is possible I could be hit by a bus while walking on a street – yes it is (something like 45–55,000 to one apparently). Is it possible I could win the major prize in a lottery – extremely unlikely being somewhere between 8 million to 76 million to 1. So, while the answer can be an affirmative – it’s possible – the parameters are meaningless because you haven’t proved the first part of your question and hence we can’t calculate the probability.
The ‘if not – why not’ is a rhetorical tool from which you are seeking to evoke a particular reaction from an audience in that, if not
CONJUNCTION [with neg]
Probably not as all the original cases started at the wet market.
Recently this came to my attention, but was proved to be fake news.
The Ministry of Foreign Affairs of China has officially demanded that the United States explain that biohazard containers were found blah blah blah ….. blah blah Their contents are now being studied by Chinese military biologists.
…. But this might be false…. and indeed it was.