Step 1: Recall event. At Wimbledon 2012, Indian tennis legend Leander Paes partnered with Russian player Elena Vesnina. Step 2: Achievement. They won the Mixed Doubles title, adding to Paes's multiple Grand Slam victories. Step 3: Elimination of wrong options.
- (a) Frederik Nielsen won men's doubles, not mixed.
- (b) Jonathan Marray paired in men's doubles, not mixed.
- (d) Mike Bryan won in men's doubles events. Step 4: Conclude. The winning pair is Leander Paes and Elena Vesnina.
\[
\boxed{\text{Leander Paes and Elena Vesnina}}
\]