Answer:
e. grapevine; informal
Step-by-step explanation:
As we know that there are two types of informal communication i.e. grapevine and the management by the wandering around. Here grapevine represents the non-official communiation that shows a network of the gossip plus rumor that we called as an employee langugae
Therefore as per the given situation, the option e is correct and hence, the same is to be considered