Explanation:

- Human activities are generally divided into three main types: Economic, Non-economic, and sometimes Mechanical or Recreational activities.

- Option 1: One

- ? Not correct, as human activities are not classified under just one type.

- Option 2: Two

- ? Not correct, although some sources mention just economic and non-economic, the more accurate classification refers to three types.

- Option 3: Three

- Correct! Human activities are usually categorized as Economic, Non-economic, and Mechanical/Recreational.

- Option 4: Four

- ? Not correct, as the standard grouping is not into four types.

Correct Answer: Option 3: Three