(1 point) Yesterday, on Facebook, one of Sarah's friends suggested that she spread the word about Mia Bella Boutique, an online company that designs hats and shoes. If Sarah's efforts generate 25 more people to spread the word, Sarah will receive 30% off her order. Mia Bella is utilizing ______, an effective strategy for increasing awareness and market share for web-based businesses. A) viral voice B) affiliate marketing C) friend to foe marketing D) guerilla marketing