Which one of the following lines is written in iambic pentameter?

A. "I lift my lamp beside the golden door"

B. "When the proofs, the figures, were ranged in columns before me"

C. "Not that the pines are darker there"

D. "And sorry I could not travel both"

The only line among these which is written in iambic pentameter is A) "I lift my lamp beside the golden door."

This line has 10 syllables, which means it has 5 meters (to count the number of meters, you first count the number of syllables and then divide that number by 2). Since it has 5 meters, and the Greek word for 5 is penta, it must be an iambic pentameter.