You will be given a definition of a task first, then some input of the task.
In this task, you're given text messages in natural language. Your task is to classify those text messages based on their content into two classes: (1) Spam and (2) Ham messages. If the content of the given message is irrelevant to the receiver or is equally relevant to many other potential recipients then it must be labeled as ‘spam’, otherwise, it should be labeled as ‘ham’.

There generally isn't one. It's an uncountable noun - u in the dictionary. pieces of research?
Output:
ham