D would be the answer because an imperative sentence is more of a request
Since we are talking about the past, the word 'was' will be used to fill the blank space.
Thesis: Your topic + aspect + your position on that aspect
Example:
Your topic = Homeless people
Aspect = Many homeless people in America
Your position = [your point]
(Your point as in wanting to help out the homeless, or what you can people can do to help, etc.)
So with this, your thesis could be something like:
"The Numbers of Homeless people in America is rising and I think that... [insert your point here]"
