Answer: not affecting the manager's bonus
Step-by-step explanation:
Under Variable costing, fixed manufacturing overhead is not charged on inventories produced or not sold for the year which means that regardless of inventory level, the relevant inventory here when it comes to calculating operating profit is the one that was sold.
The manager's bonus will therefore not change as a result of higher inventory levels. Were this absorption costing where fixed overhead was charged to inventory that was not sold, the manager's bonus would increase because the higher inventory level would absorb more of the cost.