Triple

Given a phrase, classify it is english named entity (e.g., persons, organizations, works of art) in Latin script, or not (e.g., literals, dates, URLs, verbose phrases). For disambiguation, the statement where the phrase occurs as object is also given. Please return a JSON object with `phrase` (string, the phrase being analyzed) and `is_ne` (boolean, indicating whether the phrase is a Named Entity).

Phrase: Tsar of Bulgaria | Statement: [Bulgarian royal family, monarchicalTitle, Tsar of Bulgaria]

Target entity: Tsar of Bulgaria
Context triple: [Bulgarian royal family, monarchicalTitle, Tsar of Bulgaria]

• A. Ferdinand I of Bulgaria
  Ferdinand I of Bulgaria was the ruler who transformed Bulgaria from a principality into an independent kingdom, serving as its prince and later tsar from 1887 to 1918 and leading the country through the Balkan Wars and World War I.
• B. Boris III of Bulgaria
  Boris III of Bulgaria was the Tsar of Bulgaria from 1918 to 1943, known for steering his country through the interwar period and most of World War II while attempting to maintain a degree of independence from Nazi Germany.
• C. Peter I of Bulgaria
  Peter I of Bulgaria was a 10th-century tsar of the First Bulgarian Empire known for his long and relatively peaceful reign, during which Bulgaria strengthened its Christianity and diplomatic ties with Byzantium.
• D. Alexander I of Bulgaria
  Alexander I of Bulgaria was the first modern ruler of an autonomous Bulgaria after Ottoman rule, reigning as prince from 1879 to 1886 during the formative years of the Bulgarian state.
• E. Peter IV of Bulgaria
  Peter IV of Bulgaria was a medieval Bulgarian tsar who played a key role in the restoration of Bulgarian independence and the establishment of the Second Bulgarian Empire in the late 12th century.
• F. None of above. chosen
• G. Unsure - the case is ambiguous/there is not enough information to decide.

Generate a one-sentence description of the target entity. 
You are given a context triple in the form (subject, predicate, object), where the object is the target entity. 
# Instructions
Use the triple to infer relevant information about the entity. Describe the entity based on what is most defining, well-known. 
Avoid repeating the information from the triple, unless really essential.
# Response Format
Return only the sentence: "Description: [one-sentence description of the target entity]"

Entity: Tsar of Bulgaria
Triple: [Bulgarian royal family, monarchicalTitle, Tsar of Bulgaria]

The Tsar of Bulgaria was the hereditary monarch and head of state of the Kingdom of Bulgaria until the abolition of the monarchy in 1946.

Target entity: Tsar of Bulgaria
Target entity description: The Tsar of Bulgaria was the hereditary monarch and head of state of the Kingdom of Bulgaria until the abolition of the monarchy in 1946.

• A. Ferdinand I of Bulgaria
  Ferdinand I of Bulgaria was the ruler who transformed Bulgaria from a principality into an independent kingdom, serving as its prince and later tsar from 1887 to 1918 and leading the country through the Balkan Wars and World War I.
• B. Boris III of Bulgaria
  Boris III of Bulgaria was the Tsar of Bulgaria from 1918 to 1943, known for steering his country through the interwar period and most of World War II while attempting to maintain a degree of independence from Nazi Germany.
• C. Peter I of Bulgaria
  Peter I of Bulgaria was a 10th-century tsar of the First Bulgarian Empire known for his long and relatively peaceful reign, during which Bulgaria strengthened its Christianity and diplomatic ties with Byzantium.
• D. Alexander I of Bulgaria
  Alexander I of Bulgaria was the first modern ruler of an autonomous Bulgaria after Ottoman rule, reigning as prince from 1879 to 1886 during the formative years of the Bulgarian state.
• E. Peter IV of Bulgaria
  Peter IV of Bulgaria was a medieval Bulgarian tsar who played a key role in the restoration of Bulgarian independence and the establishment of the Second Bulgarian Empire in the late 12th century.
• F. None of above. chosen