Teaching BPSC 4.0 बिहार उच्च माध्यमिक शिक्षक भर्ती (PGT) Mock Test General Science Chemistry Organic Chemistry
The first fully synthetic fibre developed by human beings was ________.
1
Bakelite
2
Rayon
3
Nylon
4
More than one of the above
5
None of the above