"I" is in regards to yourself, you and any humans name are proper nouns that you go by. "a" is not a proper noun it is describing the quantity or the subject of the matter, Ex- [I] love it when [a] cool summer day takes place in my area.
{Bad sentence, sorry}
B, because nothing in this talks about dogs, and the main idea of the article is fish. It is more specifically about setting up a fish aquarium.
It hurts everyone idk why just find it out
