This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Ex Input:
Passage: First recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1905 the value E, the minimal energy increment of a hypothetical oscillator, was theoretically associated by Einstein with a "quantum" or minimal element of the energy of the electromagnetic wave itself. The light quantum behaved in some respects as an electrically neutral particle, as opposed to an electromagnetic wave. It was eventually called the photon. Question: Who discovered an association between the value E and quantum energy?

Ex Output:
Einstein


Ex Input:
Passage: Samurai were many of the early exchange students, not directly because they were samurai, but because many samurai were literate and well-educated scholars. Some of these exchange students started private schools for higher educations, while many samurai took pens instead of guns and became reporters and writers, setting up newspaper companies, and others entered governmental service. Some samurai became businessmen. For example, Iwasaki Yatarō, who was the great-grandson of a samurai, established Mitsubishi. Question: What kind of schools did samurai start?

Ex Output:
private schools for higher educations


Ex Input:
Passage: The urban AC stations resemble soft AC rather than hot AC; they play predominantly R&B and soul music with little hip-hop. This is reflected in many of the urban AC radio stations' taglines, such as "Today's R&B and classic soul", "The best variety of R&B hits and oldies" and "(City/Region)'s R&B leader". Urban AC's core artists include Luther Vandross, Trey Songz, Patti LaBelle, Toni Braxton, Whitney Houston, Aretha Franklin, Frank Ocean, Craig David and Mariah Carey. Question: Along with Trey Songz, Patti LaBelle, Toni Braxton, Whitney Houston, Aretha Franklin, Frank Ocean, Craig David and Mariah Carey, who is a well-known urban AC artist?

Ex Output:

Luther Vandross