At the macro scale, diamond is generally considered to show no slight deformation behavior. The consequences of any extreme attempt to deform it often occurs before a brittle fracture occurs before it can reach visible deformation. This makes it useful in some applications that may withstand mechanical deformation. Limited. In order to perform nano-scale mechanical tests on it, the research team designed a unique set of nano-mechanical experimental methods to conduct quantitative "compression-bending" tests on single crystal and polycrystalline diamond nanoneedle samples. The results show that the test The samples can achieve large deformations that are tens of times higher than macro-diamonds, and can be fully recovered within a large range. The experimental results have been simulated and analyzed to confirm that the elastic deformation of the single-crystal diamond nanoneedle on the tensile side reaches about 9 The corresponding intensity is also close to its theoretical limit. This discovery will help further expand the application of diamond in biomedical fields such as drug delivery, biodetection and imaging. The following options correctly understand the above text:. ['In this experiment, the elastic deformation of the polycrystalline diamond nanoneedle sample on the tensile side reached about 9%.', 'At the macro scale, any extreme attempted behavior will not allow the diamond to reach visible deformation.', 'At present, the application of diamond in biomedical fields such as biological detection and imaging is more limited.', 'The experimental results found that the unique nanomechanical experimental method benefited from the design of the research group.']