Which one of the following more likely constitutes a business?

a.

An economist in Hobart has ten sheep, eight hens, four dogs and two horses on his country retreat.

b.

An Adelaide scientist collects stamps in her spare time, buying and selling stamps through the internet, making a regular $26,000 profit each year.

c.

A dentist restores antiques in St Kilda in his spare time out of enjoyment and occasionally sells a piece and makes an annual profit of $50.

d.

A doctor reconditions old model planes and sells them at almost cost, barely making a profit.