Answer:
So far what I know about Zebra is he's a runner. In the first paragraph, it states how they started to call him Zebra before or after he started running. It also looks like Zebra enjoys zebras. In the third and fourth paragraphs, it states how he went to see zebras in the zoo and in a movie. That's most likely how he fell in love with zebras. That's what we know about Zebra judging from the 4 given paragraphs.
C. Whales. Because normally it is the first word and even though mammals would be considered a subject, it isn't the main subject.
Hope this helps!! :)
