Can you throw away a trashcan

yes

Explanation: Throw your trash can away by placing it upside down to demonstrate that it's empty and clearly labeling it for pick up. Or, instead of throwing it away, recycle your trash can at a local recycling facility or transform it into a storage or compost bin.

the correct answer is a. how to make proposal that works.

indeed, the register is quite formal and the tone is especially objective as it avoids the use of the first and second person singular (i, you) and opts instead for the third person plural which is more impersonal and focuses on the data and the argument that is being developed by the author. the formality adds the impression of respectability to the work and the impersonality adds objectivity to it.