Subject: Business Income vs. Capital Gain

During 2020, Sandra Von Arb acquired a four-unit apartment building for $230,000. While it was her intention to operate the buildings as a rental property, one month after her purchased she received an unsolicited offer to purchase the building for $280,000. She accepts the offer. Should the $50,000 be treated as acapital gain or as business income?. Justify your conclusion.