3901
Micro computed tomography ( CT ) , which is capable of assessing the internal defects and recovering the 3D representation of a structure , was used as a validation method to correlate the features identified in the optical images .
 process characterization: computed tomography; enabling technology: CT; concept or principle: defects; concept or principle: 3D; concept or principle: structure; material: as; concept or principle: validation; process characterization: optical; concept or principle: images
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
 Entities: computed tomography, CT, defects, 3D, structure, as, validation, optical, images 
Answer:
 process characterization: computed tomography; enabling technology: CT; concept or principle: defects; concept or principle: 3D; concept or principle: structure; material: as; concept or principle: validation; process characterization: optical; concept or principle: images