user: Question: What is the incumbent for 1974?
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Massachusetts 1', 'Silvio Conte', 'Republican', 1958.0, 'Re-elected', 'Silvio Conte (R) 82.7% John R. Arden (D) 17.3%']
SQL:

assistant: SELECT "Incumbent" FROM "Table" WHERE "First elected" = 1974.0;