Final answer:
Undermining a co-worker's work and acting rudely to older customers are behaviors that can be considered harassment, as they can create a hostile work environment or discriminate based on protected classes. Speaking kindly to co-workers or deciding who to help first do not constitute harassment.
Step-by-step explanation:
Among the behaviors listed, undermining a co-worker's work and acting rudely to older customers can be considered forms of harassment. Undermining a co-worker's work can create a hostile work environment and may include actions such as sabotage, spreading rumors, or failing to provide necessary information. This kind of behavior can interfere with a person's job performance and create an intimidating atmosphere, which aligns with the legal definition of harassment. Actively choosing to act rudely towards older customers may also fall under harassment if it's based on age, which is one of the protected classes according to the Equal Employment Opportunity Commission (EEOC) and can make customers feel unwelcome or discriminated against.
Speaking kindly to co-workers and deciding whom to help first are not considered harassment. These are either positive interactions or neutral decisions that do not contribute to creating a hostile or offensive environment.
It is also important to note sexual harassment and other types of harassment such as quid pro quo and hostile work environment scenarios, which are illegal when they create adverse work conditions or result in adverse employment decisions. Moreover, actions that may seem minor, such as insensitive jokes or comments, can lead to harassment if they become frequent or severe.