Read the following passage written by a teen hero: i want to be a vocal advocate for nature. i reject the idea that i am too young to make a difference. i recently a group with a river cleanup. i was mortified to see the destruction of animals and plants. when i got home, i composed a letter to my state politicians and asked them to allocate more money to the local river cleanup effort. i believe my vocation is to citizens see that we are at a junction. we can decide to subject nature to abuse, or we can decide to be a benefactor to nature. i won't let obstacles detract from my mission. in sentence 4, the root in the word "mortified" means
frustration
death
disappointment
sadness.