How do metaphors and extended metaphors differ?

A. While a metaphor is limited in length, an extended metaphor is developed over the course of a poem.

B. While a metaphor describes the way someone thinks or feels, an extended metaphor compares multiple unlike things.

C. While a metaphor conveys a set of ideas, an extended metaphor conveys a single idea across the poem.

D. While a metaphor makes a comparison, an extended metaphor shows the attitude of a text toward its subject