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.

Example Input: Passage: Avicenna was born c. 980 in Afšana, a village near Bukhara (in present-day Uzbekistan), the capital of the Samanids, a Persian dynasty in Central Asia and Greater Khorasan. His mother, named Setareh, was from Bukhara; his father, Abdullah, was a respected Ismaili scholar from Balkh, an important town of the Samanid Empire, in what is today Balkh Province, Afghanistan, although this is not universally agreed upon. His father worked in the government of Samanid in the village Kharmasain, a Sunni regional power. After five years, his younger brother, Mahmoud, was born. Avicenna first began to learn the Quran and literature in such a way that when he was ten years old he had essentially learned all of them. Question: What present-day country was Avicenna born in?
Example Output: Uzbekistan

Example Input: Passage: Modern electrification systems take AC energy from a power grid which is delivered to a locomotive and converted to a DC voltage to be used by traction motors. These motors may either be DC motors which directly use the DC or they may be 3-phase AC motors which require further conversion of the DC to 3-phase AC (using power electronics). Thus both systems are faced with the same task: converting and transporting high-voltage AC from the power grid to low-voltage DC in the locomotive. Where should this conversion take place and at what voltage and current (AC or DC) should the power flow to the locomotive? And how does all this relate to energy-efficiency? Both the transmission and conversion of electric energy involve losses: ohmic losses in wires and power electronics, magnetic field losses in transformers and smoothing reactors (inductors). Power conversion for a DC system takes place mainly in a railway substation where large, heavy, and more efficient hardware can be used as compared to an AC system where conversion takes place aboard the locomotive where space is limited and losses are significantly higher. Also, the energy used to blow air to cool transformers, power electronics (including rectifiers), and other conversion hardware must be accounted for. Question: What nowdays electrification systems can use?
Example Output: DC motors which directly use the DC or they may be 3-phase AC motors

Example Input: Passage: There are traditions long associated with football games. Students growl like wildcats when the opposing team controls the ball, while simulating a paw with their hands. They will also jingle keys at the beginning of each kickoff. In the past, before the tradition was discontinued, students would throw marshmallows during games. The Clock Tower at the Rebecca Crown Center glows purple, instead of its usual white, after a winning game, thereby proclaiming the happy news. The Clock Tower remains purple until a loss or until the end of the sports season. Whereas formerly the Clock Tower was lighted only for football victories, wins for men's basketball and women's lacrosse now merit commemoration as well; important victories in other sports may also prompt an empurpling. Question: What noise do students make when the opposing team has control of the football?
Example Output:
growl