Answer:
c. Sales to other segments.
Explanation:
Segment operating income refers to segment's net revenue (sales) less losses (cost of revenue and operating cost). Segment operating income does not involve general corporate expense,income tax expense, gain or loss on discontinued operations.
Segment operating income is derived from sales activities.
Since
Segment operating income= Segment revenue (sales) - Expenses
Means Sales (revenue) to other segments is considered and used to calculate the segment operating income.