With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Machu Picchu was part of an empire in pre-columbian America.
text_B: Sidney Carter Jelinek -LRB- March 18 , 1899 -- March 9 , 1979 -RRB- was an American rower who competed in the 1924 Summer Olympics .. American. United States. rower. Rowing ( sport ). 1924 Summer Olympics. 1924 Summer Olympics. In 1924 he won the bronze medal as member of the American boat in the coxed fours event .. coxed fours. Rowing at the 1924 Summer Olympics. American. United States
not_related.