But Bella was barely listening . She was watching the instructor , only a few years older than her mere fourteen years , prepare for another serve . His muscles rippled through his shirt as he raised a sculpted arm and swung through .

Generate a question about the above context.
Why is Bella not a disciplined student at the moment ?
Choices:
(i). None of the above choices ..
(ii). Bella is enamored with a guy ..
(iii). Bella is bored with studying ..
(iv). Bella is careless with studies ..