Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

 What is commonly called pepper in reality comes from two very different families of plants. Black and white pepper both come from the fruit of the Piper nigrum, a vine with fruits called peppercorns. The peppercorns turn from green to red as they ripen and finally blacken as they dry out. The dried-out peppercorns are ground to obtain black pepper. White pepper, which has a more subtle flavour than black pepper, comes from the same peppercorns as black pepper. To obtain white pepper, the outer hull of the peppercorn, the pericarp, is removed before the peppercorn is ground. Red and green pepper, on the other hand, come from a completely different family from black and white pepper. Red and green peppers are from the genus Capsicum. Plants of this type generally have tiny white flowers and fruit which can be any of a number of colours, shapes and sizes. These peppers range in flavour from very mild and sweet to the most incredibly burning taste imaginable. Bell peppers are the mildest, while habanros are the most burning.

 Christopher Columbus is responsible for the present-day confusion over what pepper is. The Piper nigrum variety of pepper was highly valued for centuries, and high demand for pepper by Europeans was a major cause of the fifteen-century push to locate ocean routes to the spice-growing regions of Asia. When Columbus arrived in the New World in 1492, he was particularly interested in finding black pepper because of the high price it would command in Europe. Columbus came across plants from the Capsicum family in use among people of the New World, and he incorrectly identified them as relatives of black pepper. Columbus introduced the spicy Capsicum chili peppers to Europeans on his return from the 1492 voyage, and traders later spread them to Asia and Africa. These Capsicum peppers have continued to be called peppers in spite of the fact that they are not related to the black and white pepper of the Piper nigrum family.

 The pronoun “them” refers to __________.