सिलाई मशीन का कौन सा उपकरण धागे को पर्याप्त मात्रा में आगे बढ़ाता है और सिलाई के लूप/टांके को कसता है?

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The essential purpose of chemical testing in the textile industry is to detect the presence of restricted substances such as formaldehyde, azo dyes, and heavy metals. Reason R: These specific chemical evaluations are primarily intended to measure the physical properties of the fabric, such as dimensional stability and air permeability. In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: The systematic evaluation of yarn strength and evenness is considered a critical quality control measure in textile manufacturing to ensure the long-term performance of the final garment. Reason R: The tensile strength and uniformity of yarn are foundational properties that directly dictate the overall durability and the prevention of physical defects in the finished textile material. In the light of the above statements, choose the most appropriate answer from the options given below: