Apple Co. BPP Kit (Performance Measurement)

The following scenario relates to questions 334 – 338.

An investment centre in Apple Co generates a profit of $24,000.You have been given the following additional information about the investment centre.

Working capital 20,000
Non-current assets at cost 230,000
Accumulated depreciation (170,000)
Carrying value 60,000

(337) Apple Co operates a transfer pricing system between two divisions based on market price. Are the following statements about this true or false?

(1) The market price acts as an incentive to use up any spare capacity
in the selling division of Apple Co. (False)

(2) Using the market price as the transfer price encourages selling
and buying decisions which appear to be in the best interests of
the division’s performance. This leads to the company as a whole
achieving optimal results as each division optimises its
performance. (True)

Hello tutor!!
About statement 1, they are saying it is False because market price doesn’t always use as an incentive for selling division if they have any spare capacity because market price may contain some undesirable mark up for selling division and in contrast they could go for some opportunity cost which would become incentive for them. But if they have spare capacity then why do they need any opportunity cost and it is the same Market price on which selling division is selling their product external customers then why not disincentive for external and disincentive only for internal ?

And also in 2nd statement, they are saying that market price can encourage both division.
Please help me to understand this.