Correct Answer:
B. Sorrow
Grief is defined as intense sorrow, especially caused by someone's death. The most fitting synonym among the options is Sorrow, which directly describes a feeling of deep distress or sadness. While Happiness represents the complete opposite emotional state of joy and contentment, and Love is an emotion of deep affection distinct from sadness, neither accurately reflects the profound sadness inherent in grief. The question specifically asks for a synonym, and 'Sorrow' perfectly captures the essence of the emotional pain and distress associated with grief, making it the unequivocally correct answer.