What are the five guidelines to scansion?

The last foot (the anceps) always consists of two syllables so mark it so immediately. You can

regard the very last syllable as an unknown vowel length and mark it as an X (it will normally be

pronounced long no matter what)

2. The second to last foot is almost always a dactyl so mark it so immediately

3. The first syllable of every line of poetry is long no-matter-what so mark it so immediately.

4. The thesis (first syllable) of a foot is always long

5. The arsis (the second half) of a foot will either be one long or two shorts: there can be no

mixing and matching in the second half of the foot

Explanation:

i think the answer is c

b is the answer.   i sat on the lumpy sofa, totally exhausted, with a bad taste in my mouth, wondering what i should do next.