Which word indicates intense emotion?

The word "ardent" is the correct choice as it conveys a strong and passionate intensity of emotion. It is typically used to describe feelings that are fervent or enthusiastic, often in the context of love, support, or dedication. When someone is described as ardent, it implies that their emotions are vibrant and deeply felt, reflecting an eager and fervid nature. This strong connection to intense feelings makes "ardent" the best option among the choices provided.

In contrast, the other terms suggest the absence of strong emotional involvement. "Indifferent" indicates a lack of interest or concern, while "detached" refers to being emotionally separated or uninvolved. "Dispassionate" denotes a state of being free from emotional involvement, often characterized by rational or objective thinking. Thus, these words diverge from the concept of intense emotion that "ardent" embodies.