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: Mstislav Yuryevich | Statement: [Yuri Dolgorukiy, child, Mstislav Yuryevich]

Target entity: Mstislav Yuryevich
Context triple: [Yuri Dolgorukiy, child, Mstislav Yuryevich]

• A. Daniil Aleksandrovich of Moscow
  Daniil Aleksandrovich of Moscow was a medieval Russian prince, the youngest son of Alexander Nevsky, who became the first Prince of Moscow and laid the foundations for its future rise.
• B. Yury Ivanovich of Dmitrov
  Yury Ivanovich of Dmitrov was a Russian prince of the late 15th–early 16th century, known as a younger son of Grand Prince Ivan III and a regional ruler within the centralized Muscovite state.
• C. Vasily Christianovich
  Vasily Christianovich was an engineer and architect known for his work on notable 19th-century structures in Saint Petersburg, Russia.
• D. Yury of Moscow
  Yury of Moscow was a Grand Prince of Moscow and influential early 14th-century Russian ruler known for his power struggles over the Vladimir-Suzdal throne and his role in the rise of Moscow.
• E. Mikhail Danilovich of Moscow
  Mikhail Danilovich of Moscow was a medieval Russian prince from the ruling house of Moscow, active during the formative period of the principality’s rise in northeastern Rus’.
• 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: Mstislav Yuryevich
Triple: [Yuri Dolgorukiy, child, Mstislav Yuryevich]

Mstislav Yuryevich was a medieval Rus' prince, best known as one of the sons of Yuri Dolgorukiy and a member of the ruling Rurikid dynasty.

Target entity: Mstislav Yuryevich
Target entity description: Mstislav Yuryevich was a medieval Rus' prince, best known as one of the sons of Yuri Dolgorukiy and a member of the ruling Rurikid dynasty.

• A. Daniil Aleksandrovich of Moscow
  Daniil Aleksandrovich of Moscow was a medieval Russian prince, the youngest son of Alexander Nevsky, who became the first Prince of Moscow and laid the foundations for its future rise.
• B. Yury Ivanovich of Dmitrov
  Yury Ivanovich of Dmitrov was a Russian prince of the late 15th–early 16th century, known as a younger son of Grand Prince Ivan III and a regional ruler within the centralized Muscovite state.
• C. Vasily Christianovich
  Vasily Christianovich was an engineer and architect known for his work on notable 19th-century structures in Saint Petersburg, Russia.
• D. Yury of Moscow
  Yury of Moscow was a Grand Prince of Moscow and influential early 14th-century Russian ruler known for his power struggles over the Vladimir-Suzdal throne and his role in the rise of Moscow.
• E. Mikhail Danilovich of Moscow
  Mikhail Danilovich of Moscow was a medieval Russian prince from the ruling house of Moscow, active during the formative period of the principality’s rise in northeastern Rus’.
• F. None of above. chosen