user: Question: What is the lowest stage when the yellow jersey is Ronan Pensec?
Columns: ['Year', 'Stage', 'Start of stage', 'Distance (km)', 'Category of climb', 'Stage winner', 'Nationality', 'Yellow jersey', 'Bend']
Types: ['text', 'real', 'text', 'text', 'text', 'text', 'text', 'text', 'real']
Sample row: ['2013 †', 18.0, 'Gap', '172.5', 'HC', 'Christophe Riblon', 'France', 'Chris Froome', 15.0]
SQL:

assistant: SELECT MIN("Stage") FROM "Table" WHERE "Yellow jersey" = 'Ronan Pensec';