<h2>
Answer:</h2>
<em><u>(a) Is it an output from the system? </u></em>
<em><u>(d) Is it a synonym of an existing thing?</u></em>
<h2>
Step-by-step explanation:</h2>
In the question,
We have a list of nouns and we need to determine whether a particular noun should be excluded by identifying particular noun as an important 'thing'.
So, to identify it as a noun we can ask two questions which will distinguish between the same.
<u>(a) Is it an output from the system? </u>
It is one of the questions that can be asked because if the thing is an output from a system it will be definitely existing in real therefore, we can identify from this.
<u>(d) Is it a synonym of an existing thing?</u>
By asking this we can also confirm whether a particular thing is a noun or not because if the thing will be a synonym for an already existing material, it definitely will be a Noun.
<em><u>Therefore, the correct option is (a) and (d).</u></em>
