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 money is used by the country that uses power plug type BS 546? 
Knowledge Triplets: Power plug Type F, engineering.power_plug_standard_type.compatible_power_systems, m.08nyn6h
BS 546, common.topic.notable_types, Power plug standard type
m.08nyn6h, engineering.mains_power.compatible_plugs, Power plug Type F
Afghan afghani, user.avh.default_domain.ellerdale_topic.ellerdale_id, 009a-3300
Power plug standard type, type.type.domain, Engineering
BS 546, common.topic.article, m.08cmzh
m.0r0ryrv, dataworld.gardening_hint.last_referenced_by, Afghan afghani
Afghan afghani, finance.currency.countries_used, Afghanistan
BS 546, engineering.power_plug_standard_type.compatible_power_systems, m.08nyn6h
m.08nyn6h, engineering.mains_power.compatible_plugs, BS 546
Power plug standard type, freebase.type_profile.strict_included_types, Topic
Power plug standard type, type.type.properties, Plug standards
m.08nyn6h, engineering.location_with_mains_power.mains_power_standards, Afghanistan
Afghanistan, engineering.location_with_mains_power.mains_power_standards, m.08nyn6h
Power plug Type C, common.topic.notable_types, Power plug standard type
Power plug standard type, freebase.type_hints.included_types, Topic
Afghan afghani, finance.currency.currency_code, AFN
afghani.noun.01, base.wordnet.synset.equivalent_topic, Afghan afghani
Power plug Type F, common.topic.notable_types, Power plug standard type
BS-546-3-pin-plugs, common.image.appears_in_topic_gallery, BS 546
m.08nyn6h, engineering.mains_power.location, Afghanistan
Power plug standard type, common.topic.article, m.08nxyfr
m.08nyn6h, engineering.mains_power.compatible_plugs, Power plug Type C
BS 546, common.topic.notable_for, g.1256d4nr_
Power plug Type C, engineering.power_plug_standard_type.compatible_power_systems, m.08nyn6h
Power plug standard type, type.type.expected_by, Type
Power plug standard type, type.type.expected_by, Compatible plugs
BS 546, common.topic.image, BS-546-3-pin-plugs
BS-546-3-pin-plugs, common.image.size, m.02gfzrt
Afghanistan, location.country.currency_used, Afghan afghani
BS 546, engineering.mains_power.compatible_plugs, m.08nyn6h
Afghan afghani, finance.currency.prefix_symbol, ؋;
Power plug standard type, type.type.properties, Compatible power systems
Afghanistan, location.country.currency_used, Afghan afghani

Answer: Afghan afghani