The correct options are
A Cotton - natural
D Rayon - synthetic
Fibres obtained from animals and plants are called natural fibres.
1. Wool - obtained from the hair of animals like sheep, yak, alpaca and camel.
2. Cotton - obtained from the seeds of cotton plant.
Fibres which are man-made are called artificial or synthetic fibres. These fibres are made from chemicals. For example, rayon, nylon, polyester, etc.