Final answer:
The single mother is experiencing role strain and role conflict, where her responsibilities at work and as a single parent overlap and compete, leading to significant stress.
Step-by-step explanation:
The role stressors responsible for the single mother’s feeling of inefficiency include role strain and role conflict. As a single parent, she has to juggle multiple responsibilities such as cooking, cleaning, and providing moral guidance, which collectively contribute to role strain.
At the same time, her professional responsibilities as a store manager often conflict with her parental duties, leading to role conflict. Situations where work deadlines collide with a child's needs exemplify the day-to-day manifestations of this conflict.
Additionally, stressors such as job security, work overload, and lack of support compound the stress experienced by women who must balance work and family roles, which is arguably greater than that experienced by men due to societal expectations.