The response to multifactor values is rigid. Rigid instinct (also called the unconditioned reflex) refers to several different tropism in a certain direction organically to form a complete reflex arc reaction mode, it is congenital formation of lower animals, to determine the external stimulation produced by the reaction of the relatively fixed form. Rigid instincts are organisms after a long period of natural selection, gradually formed the low passively adapt to the environment of a kind of way of life, it is born, determined by the genetic factors, to appear without the need for training the day after tomorrow. For example, mechanical stimulation of the coelenterates and arthropods; The newborn's grip reflex, sucking reflex and adult knee jerk reflex, scratching reflex, etc. Instinct is the development form of tropism, rigidity of compound stimuli from a specific things comprehensive response, it makes the organism and the external environment to produce a higher level of coherence, formation of more advanced orderly structure. Anyway, rigid instinct is lower biological things outside of the value of multiple factors is the primary way of ordering reaction, is on the tropism, extension, and the synthesis, make tropism has more purposeful, tropism is get distillation. The fund's fourth consultation underlines the enormous uncertainty facing Britain in the ambitious task of negotiating an exit from the eu. Data released by the American petroleum institute (API) showed that U.S. crude oil inventories fell 5.2 million barrels in the week ended Dec. 15, down from an expected 35.18 million barrels. Refinery inventories fell more than expected, while gasoline inventories rose, but were less than expected. The overall API data is good and good for oil prices.