In which work of John Milton does the character 'Delilah', appear?

Option 4 : Samson Agonistes

The correct answer is Samson Agonistes. 

• Samson Agonistes is a tragic closet drama by John Milton, which was published in combination with Milton's Paradise Regained in 1671. 
• On the title page, Milton wrote that the piece was a "Dramatic Poem" rather than a drama, as he did not want it to be performed on stage. However, he realized that the character of Samson would lend itself best to the stage and teach a lesson to common people. 
• Samson Agonistes draws on the story of Samson from the Old Testament, especially from the Book of Judges, 13-16. Milton's construction of the character emphasizes Samson as a warrior or an athlete. 
• The play, like Milton's earlier work Comus, advocates for chastity; Samson has been captured by the Philistines, had his hair cut off and his eyes cut out. He realizes that he has suffered so much due to his desire for, his lust towards his wife Delilah, for which God has punished him.
• Thus we understand that Delilah is a character in Samson Agonistes. 

​Therefore, Option 4 is the correct answer.

•  It is generally thought that Samson Agonistes was begun around the same time as Paradise Regained but was completed after the larger work. 
• Samson Agonistes produces a negative portrayal of love and love's effects. Women, and men's desire for women, are connected to idolatry against God and the idea that there is no possibility for the sacred within the bonds of marital love. 
• Milton shows that like Adam, who was convinced to eat the Fruit of the Forbidden Tree by his wife Eve, Samson is also seduced by his wife Delilah. He is punished by God's wrath, through blindness, because of his sexual desires. 

•  The Masque of Comus written in 1634, is also a creative work where Milton argues for chastity. A character simple called "The Lady" is captured by the ancient God of revelry and debauchery, Comus, who tries to seduce her with the best wine and the choicest food.
• Paradise Lost and Paradise Regained have similar theological themes similar to Samson Agonistes. Paradise Lost is about the expulsion of Mankind from the Garden of Eden following Adam and Eve's consumption of the Fruit from the Forbidden Tree; Paradise Regained is about the exploits of Jesus Christ as related in the Gospel of Luke.