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: Ferdinand I of Bulgaria | Statement: [Prince Ludwig August of Saxe-Coburg and Gotha, sibling, Ferdinand I of Bulgaria]

Target entity: Ferdinand I of Bulgaria
Context triple: [Prince Ludwig August of Saxe-Coburg and Gotha, sibling, Ferdinand I of Bulgaria]

• A. Ferdinand I of Bulgaria chosen
  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. Tsar Ivan Alexander of Bulgaria
  Tsar Ivan Alexander of Bulgaria was a 14th-century Bulgarian ruler known for presiding over a cultural and literary revival that marked one of the last great flourishing periods of the medieval Bulgarian Empire.
• C. 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.
• D. 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.
• E. 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.
• F. None of above.
• G. Unsure - the case is ambiguous/there is not enough information to decide.