user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: what observatory has a telescope platform of terrestrial? 
Knowledge Triplets: Very Large Telescope, user.avh.default_domain.ellerdale_topic.ellerdale_id, 0080-66ff
Gravitational-wave observatory, astronomy.telescope_type.telescopes_of_this_type, MiniGrail
MiniGrail, astronomy.astronomical_observatory.telescope_s, Leiden University
MiniGrail, astronomy.telescope.housed_in, Leiden University
Very Large Telescope, location.location.containedby, Chile
Very Large Telescope, astronomy.telescope.operational_platform, Terrestrial
Very Large Telescope, astronomy.telescope.operational_period, m.0j5z1s3
m.0r1l3bk, dataworld.gardening_hint.last_referenced_by, Very Large Telescope
Very Large Telescope, location.location.geolocation, m.0cnqq5f
Terrestrial, astronomy.telescope_platform.telescopes_based_on_this, EMBRACE
Terrestrial, astronomy.telescope.operational_platform, MiniGrail
Terrestrial, astronomy.telescope_platform.telescopes_based_on_this, MiniGrail
EMBRACE, astronomy.telescope.operational_platform, Terrestrial
Terrestrial, astronomy.telescope_platform.telescopes_based_on_this, Very Large Telescope
Very Large Telescope, astronomy.telescope.type_of_telescope, Optical telescope
Very Large Telescope, astronomy.astronomical_observatory.telescope_s, Paranal Observatory
Very Large Telescope, astronomy.telescope.housed_in, Paranal Observatory
Chile, location.location.contains, Very Large Telescope
Very Large Telescope, base.exoplanetology.telescope.exoplanetologytool, true
Leiden University, astronomy.astronomical_observatory.telescope_s, MiniGrail
MiniGrail, astronomy.telescope.type_of_telescope, Gravitational-wave observatory
MiniGrail, astronomy.telescope.operational_platform, Terrestrial
Paranal Observatory, astronomy.astronomical_observatory.telescope_s, Very Large Telescope
Optical telescope, astronomy.telescope_type.telescopes_of_this_type, Very Large Telescope

Answer: Leiden University
Paranal Observatory