Fast-tracking and crashing are schedule compression techniques used to recover time, but both commonly increase project risk. Fast-tracking overlaps activities that were originally sequential, which can introduce rework, quality issues, and coordination failures if assumptions change or outputs are incomplete when successors begin. Crashing adds resources or increases effort to shorten durations, which can lead to higher costs, reduced productivity due to onboarding/communication overhead, and increased defect rates if work is rushed. Therefore, a likely secondary result of either technique is an increase in project risk (B). A decrease in cost (A) is unlikely-crashing usually increases cost, and fast-tracking can increase costs due to rework.
Additional scope (C) is not a direct result of schedule compression; scope changes require approval through change control. Additional resources (D) may occur with crashing but not necessarily with fast-tracking, and the question asks for a result common to both methods. Increased risk is the shared, most probable secondary outcome, which must be assessed and managed before implementing schedule compression.