Whitney Houston’s biggest smashes gave pop a much-needed dose of soul. Ballads like the wrenching “I Have Nothing” and the inspirational “Greatest Love of All” revealed the balance between her voice’s towering presence and her inner tenderness; up-tempo offerings like “How Will I Know?” and “So Emotional” took her vocal prowess to the dancefloor. And her commanding cover of Dolly Parton’s “I Will Always Love You” showed she could turn other superstars’ signature songs into R&B hits that were undeniably her own.