Hey there!
First, make sure you know what an abstract noun is.
Abstract Noun-<span>a noun denoting an idea, quality, or state rather than a concrete object.
</span>
In this case, the answer is D(Logic is easily understood)
        
             
        
        
        
The correct answer of the given question above would be option B. In David Brown’s biography, “Nolan Bushnell,” the author uses the following quotes to describe Bushnell as a teenager: <span> “…he was one of the youngest ham radio operators in the country, and he did science experiments in his garage.” Hope this helps.</span>
        
                    
             
        
        
        
Answer:
B. subjunctive
Explanation:
the sentence is a subjunctive because it expresses a wish
 
        
             
        
        
        
Answer:
I have never forgotten my mother's advice. 
Explanation:
It is a proper present perfect tense