Which item is considered an example of medium?
a. the concert of a country singer
b. romance
c."the star spangled banner" written by francis scott key
d. music

D.Music

Explanation:

In arts, like literature, sculpture, film, and others mediums is considered to be the most basic form with which the artist works, for example for a painter the most basic form or tool would be the oil paint or the brush, for the musician the most basic form would be music, or the musical notes. The other options are not basic forms or tools of an art.

the president was the speaker and it was a great part of history.

explanation:

video of the national aeronautic space administration's (nasa) coverage of president john f. kennedy’s address at rice university, houston, texas, concerning the nation's efforts in space exploration. in his speech the president discusses the necessity for the united states to become an international leader in space exploration and famously states, "we choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard."