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: Mama River | Statement: [Vitim River, hasTributary, Mama River]

Target entity: Mama River
Context triple: [Vitim River, hasTributary, Mama River]

• A. Down by the River
  "Down by the River" is a long, guitar-driven rock song by Neil Young and Crazy Horse, noted for its extended jams and dark, ambiguous lyrics.
• B. Mama Said
  "Mama Said" is a 1991 rock album by American musician Lenny Kravitz that blends classic rock, soul, and funk influences and includes the hit single "It Ain't Over 'til It's Over."
• C. Mama Tried
  "Mama Tried" is a classic 1968 country song by Merle Haggard that reflects on regret and personal responsibility from the perspective of an imprisoned man.
• D. So Long Mama
  "So Long Mama" is a song by American country artist Ricky Nelson, released as the B-side to his 1972 hit single "Garden Party."
• E. Moon River
  "Moon River" is a classic, wistful ballad composed by Henry Mancini with lyrics by Johnny Mercer, famously performed by Audrey Hepburn in the film "Breakfast at Tiffany's."
• 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: Mama River
Triple: [Vitim River, hasTributary, Mama River]

The Mama River is a significant tributary in eastern Siberia that flows through remote regions of Russia before joining the Vitim River.

Target entity: Mama River
Target entity description: The Mama River is a significant tributary in eastern Siberia that flows through remote regions of Russia before joining the Vitim River.

• A. Down by the River
  "Down by the River" is a long, guitar-driven rock song by Neil Young and Crazy Horse, noted for its extended jams and dark, ambiguous lyrics.
• B. Mama Said
  "Mama Said" is a 1991 rock album by American musician Lenny Kravitz that blends classic rock, soul, and funk influences and includes the hit single "It Ain't Over 'til It's Over."
• C. Mama Tried
  "Mama Tried" is a classic 1968 country song by Merle Haggard that reflects on regret and personal responsibility from the perspective of an imprisoned man.
• D. So Long Mama
  "So Long Mama" is a song by American country artist Ricky Nelson, released as the B-side to his 1972 hit single "Garden Party."
• E. Moon River
  Moon River is a tidal river in coastal Georgia, United States, known for its scenic marshland views and association with the song of the same name.
• F. None of above. chosen