Answer:
a. the lack of ties between factory workers and senior management in a manufacturing plant
Step-by-step explanation:
Structural Holes is a concept created by Ronald Burt to refer to the lack of direct contact between two entities. That is, it is used in sociology to designate a situation in which two individuals, entities, or organizations are so opposed to each other that a gap is created in their direct communication process, although these individuals have something in common.
Accordingly, we can conclude that among the options given, the one that best represents a Structural Hole is the letter A.