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

The teddy bear is a child's toy, a nice soft stuffed animal suitable for cuddling. It is, however, a toy with an interesting history behind it.

Theodore Roosevelt, or Teddy as he was commonly called, was the president of the United States from 1901 to 1909. He was an unusually active man with varied pastimes, one of which was hunting. One day the president was invited to take part in a bear hunt; and as Teddy was President, his hosts wanted to ensure that he caught a bear. A bear was captured, and tied to a tree; however, Teddy, who really wanted to hunt a bear, refused to shoot the bear and, in fact, demanded that the bear be extricated from the ropes; that is, he demanded that the bear be set free.

The incident attracted a lot of attention among journalists. First a cartoon drawn by Clifford K. Berryman to make fun of this situation appeared in the Washington Post, and the cartoon was widely distributed and reprinted throughout the country. Then toy manufacturers began producing a toy bear which they called "teddy bear". The teddy bear became the most widely recognised symbol of Roosevelt's presidency.

(https://englishexercisesources.blogspot.com/2019/08/skill-8-find-definitions)

A researcher explained (23) __________ problems there are.