Under a uniform pricing strategy, a monopolist maximizes total profit when:

A monopolist maximizes total profit at the point where marginal revenue equals marginal cost. This is a fundamental principle in economics because it indicates the level of output where the additional revenue generated from selling one more unit is exactly equal to the additional cost incurred in producing that unit. At this point, the monopolist can no longer increase profit by producing additional units, as any further production would yield a marginal cost that exceeds the marginal revenue, leading to reduced profits.

By producing at the level where marginal revenue equals marginal cost, the monopolist ensures that every unit produced contributes positively to total profit. If the monopolist were to set the price equal to marginal cost, it would not consider the unique position of having market power, which allows it to influence prices above marginal costs, consequently maximizing profits. The other options do not align with this principle, as they either suggest pricing tactics that do not reflect the monopolist's ability to set prices above marginal cost or neglect the relationship between revenue and cost that fundamentally drives profit maximization.