The author uses the phrase “transitive inference” to convey which of the following?

Directions: Read the following passage and answer the question.
We have been taught that we are Homo sapiens, the sapient humans. We have also been told that we are the thinking animals, the only ones; the obvious implication being that other animals do not think. We also dare to believe that we are perhaps the finest product of evolution. Such baptism has given rise to a bloated feeling of ascendancy among us. This intellect or cognition enables us to draw inferences from information and come to a conclusion.
Jean Piaget, the Swiss philosopher and child psychologist, went so far as to call children “tiny thinking sacks”. He suggested that children’s cognitive development occurs in four stages. There is the sensory motor stage up to the age of two, when a child experiences the world around him. Then there is the pre-operational stage between the age of 2 and 7 years, when he masters motor skills. It is followed by the third stage the concrete operational one, between the age of 7 and 11. By the age of 11 he develops abstract thinking. In the operational stages, sapience takes hold and develops swiftly. This is also referred to as transitive inference.
There is, however, evidence to suggest that the domain of sapience is definitely not occupied by humans alone, and we might be just a little better off than some other creatures.
Macmillan's Magazine reminisces about a debate about evolution in 1860 between Bishop Wilberforce of Oxford and the naturalist Thomas Huxley. The Bishop, in a mocking tone, asked, “Is it through your grandfather or your grandmother that you claim descent from a monkey?” On this Mr. Huxley, slowly and deliberately replied, “I would not be ashamed to have a monkey for my ancestor; but I would be ashamed to be connected with a man who uses his great gifts to obscure the truth”.
A whole series of facts are now known which reduce the gap between humans and animals. The resemblance between humans and chimpanzees is not only external. In a study, forty years ago, Dr Jane Goodall showed that chimpanzees have traces of cognition which are comparable, at least to our children. Dr. Goodall went on to record their tool making abilities. She noticed that wild chimpanzees hunted, ate meat, resorted to warfare to extend their territory and were even capable of cannibalism. In another instance, Dr. Marc Hauser of Harvard and Thomas Geissman of University of Hanover have found out that, apes can make music – Solo and Coral, with rhythm added. Some researchers have also been able to teach chimpanzees a large number of symbols in the form of hand gestures. Behaviorally, between humans and apes, there are some startling similarities, almost too human to be true. If we look straight into a chimpanzee’s eyes, an intelligent, self-assured personality looks back at us. If they aren’t sapient, how can we be?