Which of the following is not the characteristic of medical cold chain (

1, high quality: cold chain drugs need to use refrigerated trucks or low-temperature warehouses with temperature control equipment in order to maintain the specified low temperature conditions in all aspects of circulation, which is not the characteristic of medical cold chain.

2. Complexity: The quality of cold chain drugs changes with the change of temperature and time in the circulation process. Different products must have corresponding temperature and storage time, which is not the characteristic of medical cold chain.