Step 1: Analyze the query.
The query seeks the geographical location of Mount Marapi, a volcano that has recently experienced an eruption.
Step 2: Evaluate each alternative.
- Alternative A: Mexico possesses active volcanoes; however, Mount Marapi is not situated there. - Alternative B: China has volcanic activity, but Mount Marapi is not found within its borders. - Alternative C: Panama contains a volcanic zone, but Mount Marapi is absent from this region. - Alternative D: Accurate. Mount Marapi is situated in Indonesia and ranks among the planet's most active volcanoes. - Alternative E: The United States features numerous volcanoes, but Mount Marapi is not among them.
Step 3: Determine the outcome.
Indonesia is identified as the correct answer.
Final Determination: \[\boxed{\text{D}}\]