Cassandra's mother told her, "you know you are in love when your heart beats fast and you experience that unique trembling feeling inside." this remark best illustrates the theory of emotion.

James Lange theory of emotions

Explanation:

James Lange's theory of emotions proposed that emotions are equivalent to the physiological arousal that leads to emotions like fear, anger, happiness, etc that are caused by external factors.  

This theory was opposed to the common-sense theory of experience in which cause and effect relation saw that manifested the experience of emotions. The autonomic activities and the physiological activities induced the feeling of emotions.  

For instance:

Angry bull-physiological reaction-feeling of fear

the following men who did not in the unification of italy were.

a) giuseppe mazzini

c) alexander ll

the other two men were camilo cavour and giuseppe garibaldi they the unification of italy by yielding territories in the italian unification. in 1861 italy was declared a united-nation state under the sardinian king victor immanuel ll.