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.

Passage: Old English was not static, and its usage covered a period of 700 years, from the Anglo-Saxon settlement of Britain in the 5th century to the late 11th century, some time after the Norman invasion. While indicating that the establishment of dates is an arbitrary process, Albert Baugh dates Old English from 450 to 1150, a period of full inflections, a synthetic language. Perhaps around 85 per cent of Old English words are no longer in use, but those that survived, to be sure, are basic elements of Modern English vocabulary. Question: In what century did Old English cease to be used?
11th

Passage: Flower ontogeny uses a combination of genes normally responsible for forming new shoots. The most primitive flowers probably had a variable number of flower parts, often separate from (but in contact with) each other. The flowers tended to grow in a spiral pattern, to be bisexual (in plants, this means both male and female parts on the same flower), and to be dominated by the ovary (female part). As flowers evolved, some variations developed parts fused together, with a much more specific number and design, and with either specific sexes per flower or plant or at least "ovary-inferior". Question: What did some plant parts do as they evolved?
fused together

Passage: The National Art Gallery in Yerevan has more than 16,000 works that date back to the Middle Ages, which indicate Armenia's rich tales and stories of the times. It houses paintings by many European masters as well. The Modern Art Museum, the Children's Picture Gallery, and the Martiros Saryan Museum are only a few of the other noteworthy collections of fine art on display in Yerevan. Moreover, many private galleries are in operation, with many more opening every year, featuring rotating exhibitions and sales. Question: What is the earliest period the National Art Gallery has pieces from?
the Middle Ages