Fernando Alonso drove for Ferrari from 2010-2014, where he challenged for the World Championship multiple times. His Ferrari period is particularly notable as he came close to winning titles in 2010 and 2012. While Alonso also drove for Renault (2003-2006, 2008-2009) and McLaren-Mercedes (2015-2018), the question likely refers to his famous Ferrari stint. The timing of this question (early 2010s) makes Ferrari the correct answer.