Here you go (English)
here you go in Persian is: بفرمایید.
Parallel structure means using the same pattern of words to show that at least two ideas are equally important as each other. Parallel structure can be used to create a rythem or a pattern in certain types of sentences.
Answer:
D. A DOW is a truck with scientific equipment mounted on the back of it.
Explanation:
Now, in order to answer correctly, we need to take a look at the sentence before and the sentence after this blank.
The sentence before introduces us to this new tool, its name and abbreviation.
The sentence after gives us short insight on the look of the truck.
Since this truck isn't mentioned anywhere before in the text, we can safely presume that the best fitting logical connection between these two sentences is the one which explains that this new tool is actually a truck, which is the answer D.
D) Excessive texting can be harmful to your physical health.