I believe it would be C. I loved brushing the horses and feeding the goats of course. That would be my personal choice.
The position of a topic sentence can be placed at the beginning of the paragraph, which forms a deductive order (Main topic then down to the supporting details). It can also be placed at the end of the paragraph, which forms an inductive order (supporting details before the main topic). But a topic sentence should never be placed in the MIDDLE of the paragraph.
I think you should have about 12 years of school. I hope this helps :)