What we have is a sentence equivalence question, meaning there are two right answers. To find the right answers, let us deploy the IMS's four-step technique.

STEP #1 -> STORYBOARD

Let us read and understand the story. The story talks about a young person in the possession of only an antiquated (very old) rifle and a revolutionary spirit. It further says this young person with his sole possessions forded (crossed a shallow place in) the perilous (risky/dangerous) canyon stream and wended (went) his way up the opposite banks. He did so to join forces (work together) with the insurgent (anti-establishment/rebelling against the establishment) militia (army of ordinary citizens).

Now that we know what the story is all about, let us proceed to the second step.


STEP #2 -> RELATE

We can now look for clues that tell us what the blank is dealing with. We may ask ourselves two questions, 'What is the blank dealing with'? 'What information do we have about what the blank is dealing with?' So, what is the blank dealing with? Clearly, it has something to do with this young person; what information do we have about this person? We know his spirit was revolutionary, he had a very old rifle, and he hoped to work with the rebelling army of ordinary citizens.

Now that we have an insight into what the blank is dealing with, let us proceed to the third step.

STEP #3 -> PREDICT

Based on the clues we have, let us now come up with our own word for the blank. A revolutionary person carrying a very old rifle who is all set to rebel against the establishment can be called a rebel. Therefore, 'REBEL' becomes our own word for the blank.

Now that we have come up with our own word, let us proceed to the final step.

STEP #4 -> ELIMINATE

All answer options that do not closely match with 'REBEL' can be eliminated.

(A) Myrmidon - NOT A MATCH - It means 'a faithful follower' .- ELIMINATE
(B) Rapscallion - NOT A MATCH - It means 'a rascal/scoundrel'. - ELIMINATE
(C) Defector - A CLOSE MATCH - It means 'a person who deserts one's country to join the opposing forces'. - KEEP
(D) Quisling - A CLOSE MATCH - It means 'a person who betrays one's country by working with rebelling forces.' - KEEP
(E) Deity - NOT A MATCH - It means 'a god or goddess'. - ELIMINATE
(F) Devotee - NOT A MATCH - It means 'an ardent follower or admirer'. - ELIMINATE

Hence, C and D are the right answers.