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 II of Kiev | Statement: [Roman the Great, father, Mstislav II of Kiev]

Target entity: Mstislav II of Kiev
Context triple: [Roman the Great, father, Mstislav II of Kiev]

• A. Vsevolod II of Kiev
  Vsevolod II of Kiev was a 12th-century Grand Prince of Kiev from the Olgovichi branch of the Rurikid dynasty, known for his role in the complex dynastic struggles of Kievan Rus'.
• B. Sviatoslav III of Vladimir
  Sviatoslav III of Vladimir was a 13th-century prince of Vladimir-Suzdal who briefly ruled the Grand Principality of Vladimir during the politically turbulent period following the Mongol invasion of Rus'.
• C. Sviatopolk II of Kiev
  Sviatopolk II of Kiev was a Grand Prince of Kievan Rus' in the late 11th and early 12th centuries, known for his turbulent reign marked by dynastic struggles and conflicts with neighboring powers.
• D. Sviatoslav II of Kiev
  Sviatoslav II of Kiev was an 11th-century Grand Prince of Kievan Rus', known for co-ruling the realm with his brothers and participating in the complex dynastic politics following the death of Yaroslav the Wise.
• E. Sviatopolk I of Kiev
  Sviatopolk I of Kiev was a Grand Prince of Kievan Rus' known for his violent struggle for power and the alleged murder of his half-brothers, earning him the epithet "the Accursed."
• 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 II of Kiev
Triple: [Roman the Great, father, Mstislav II of Kiev]

Mstislav II of Kiev was a 12th-century Grand Prince of Kiev from the Rurikid dynasty, known for his turbulent reign marked by internal strife and shifting political alliances among the Rus' principalities.

Target entity: Mstislav II of Kiev
Target entity description: Mstislav II of Kiev was a 12th-century Grand Prince of Kiev from the Rurikid dynasty, known for his turbulent reign marked by internal strife and shifting political alliances among the Rus' principalities.

• A. Vsevolod II of Kiev
  Vsevolod II of Kiev was a 12th-century Grand Prince of Kiev from the Olgovichi branch of the Rurikid dynasty, known for his role in the complex dynastic struggles of Kievan Rus'.
• B. Sviatoslav III of Vladimir
  Sviatoslav III of Vladimir was a 13th-century prince of Vladimir-Suzdal who briefly ruled the Grand Principality of Vladimir during the politically turbulent period following the Mongol invasion of Rus'.
• C. Sviatopolk II of Kiev
  Sviatopolk II of Kiev was a Grand Prince of Kievan Rus' in the late 11th and early 12th centuries, known for his turbulent reign marked by dynastic struggles and conflicts with neighboring powers.
• D. Sviatoslav II of Kiev
  Sviatoslav II of Kiev was an 11th-century Grand Prince of Kievan Rus', known for co-ruling the realm with his brothers and participating in the complex dynastic politics following the death of Yaroslav the Wise.
• E. Sviatopolk I of Kiev
  Sviatopolk I of Kiev was a Grand Prince of Kievan Rus' known for his violent struggle for power and the alleged murder of his half-brothers, earning him the epithet "the Accursed."
• F. None of above. chosen