Darkness settles on roofs and walls,
but the sea, the sea in darkness calls;
the imagery in these lines evokes a sense of
a laziness.
b fear.
c mystery.
d despair.

I believe the answer is: Mystery

A sense of mystery tend to be created when the situation presented in the writing seem uncertain and difficult to explain.

The use of the word darkness in both lines depict something that couldn't be easily seen/noticed and yet the usage of the words 'settles' and 'calls' means that the speaker is sure that something exist in the darkness.

ichabod crane is a fictional character and the protagonist in washington irving's short story, "the legend of sleepy hollow", first published in 1820. in popular culture, this story is sometimes retitled as "the headless horseman."