COMPREHENSION: Read the following text and decide which is the correct answer.

The rate of innovation accellerated. The Frenchman Nicolas Appert invented the can in 1810. Though it was made from glass rather than metal, it represented the birth of a long-term preservation method for food. Canned food was first put to the test by the army during the Crimean wars and during the American Civil War before it become available to consumers.
The cardboard box emerged at the end of the 19th century, a simple yet revolutionary invention. An American, Robert Gair, had the bright idea of manufacturing in bulk a pre-cut cardboard panel which, once folded, would form a box. This made the transportation of goods much easier and the box become the most widely used method of packaging at the beginning of century due to its very low price and ease of use. Today, boxes are used to supply us with fragile and high-tech equipment, such as video recorders and computers.
In 1920, the invention of transparent cellophane marked the begging of the era of plastic. Polyethylene, the first plastic used for packaging, was discovered in 1933... by mistake! Aluminium foil, which came later, made it possible to effectively seal medications and other sensitive products. From then on, a large number of technical innovations led to the continued improvement of packaging and, consequently, to increased choice of food, thus improving our everyday standard of living. In the 1940s, packaging was developed for frozen food. In 1952 aerosol came onto the market. Cans, available from the 1960s, heralded the explosion of the soft drinks market. Aseptic cartons, invented in 1961, have been used for preserving long-life milk ever since.
The continuous quest by mankind to find new methods of conserving food and transporting products has allowed us to substantially limit the loss of our resources over the course of time