Yes it is D all the way right answer
To determine the root cause of contamination
I believe A, hope I could help
It is exclamation point because for example, the person who is staying this sentence probably was astonished, or find it interesting so he/she said this sentence.
<span>The best summary of the passage is: Boston terrier breed began around 1870 in Boston with a dog named “Judge.”. A good summary must express the same information that is stated in the whole text in a few words that maintain the main idea. This summary contains all the main points of the passage that give us information of origin of Boston terriers, including the year, place and the first ancestor.<span>
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