Select the most appropriate option that can substitute the underlined word in the following sentence with its ANTONYM.
The teacher filled the students' minds with pessimistic thoughts about their futures.

The word pessimistic means tending to see the worst aspect of things or believe that the worst will happen (negative, gloomy). Its antonym must mean positive or promising.
bright: Full of hope or promise; cheerful and lively (Antonym of pessimistic).

discouraging: Causing someone to lose confidence or enthusiasm (Synonym-leaning).

cynical: Believing that people are motivated purely by self-interest; distrustful (Synonym-leaning).

desperate: Feeling or showing a hopeless sense that a situation is so bad as to be impossible to deal with.